Answer:600
Step-by-step explanation:
300,000/ 500 =600
HELP ASAP
[tex]Given that $33^{-1} \equiv 77 \pmod{508}$, find $11^{-1} \pmod{508}$ as a residue modulo 508. (Give an answer between 0 and 507, inclusive.)[/tex]
===================================================
Work Shown:
[tex]33^{-1} \equiv 77 \text{ (mod 508)}\\\\(3*11)^{-1} \equiv 77 \text{ (mod 508)}\\\\3^{-1}*11^{-1} \equiv 77 \text{ (mod 508)}\\\\3*3^{-1}*11^{-1} \equiv 3*77 \text{ (mod 508)}\\\\11^{-1} \equiv 231 \text{ (mod 508)}\\\\[/tex]
Notice how 33*77 = 2541 and 11*231 = 2541
[tex]2541 \equiv 1 \text{ (mod 508)}[/tex] since 2541/508 has a remainder of 1.
So effectively [tex]33*77 \equiv 1 \text{ (mod 508)}[/tex] and [tex]11*231 \equiv 1 \text{ (mod 508)}[/tex]
Which graph represents the solution set of this inequality?
10c + 5 < 45?
Answer:
see below
Step-by-step explanation:
10c + 5 < 45
Subtract 5 from each side
10c + 5-5 < 45-5
10c < 40
Divide by 10 on each side
10c/10 < 40/10
c < 4
Open circle at 4 and the line going to the left
Priya, Han, and Mai each measured one of the circular objects from earlier. Priya says that the bike wheel is 24 inches. Han says that the yo-yo trick is 24 inches. Mai says that the glow necklace is 24 inches. 1. Do you think that all these circles are the same size? 2. What part of the circle did each person measure? Explain your reasoning.
Answer:
Yes they are of the same size since they have the same number and standard unit of measurement (i.e 24 inches).
Each person measures the circumference of the circle.
Step-by-step explanation:
Given that :
Priya, Han, and Mai each measured one of the circular objects from earlier.
Priya says that the bike wheel is 24 inches.
Han says that the yo-yo trick is 24 inches.
Mai says that the glow necklace is 24 inches.
Do you think that all these circles are the same size?
Yes they are of the same size since they have the same number and standard unit of measurement (i.e 24 inches).
What part of the circle did each person measure?
Each person measures the circumference of the circle.
The circumference also known as the perimeter of the circle is denoted by :
C = 2π r
The circumference of a circle is the distance round the edges of the circle.
Given that C = 24
24 = 2π r
r = 24/(2π)
r = 3.8 inches
This confirms the claim that all the circle are of the same size since they possess the same radius.
Answer:
The person who answered first is WRONG
Step-by-step explanation:
I did this and these are the answers the teacher gave me:
the circles are NOT the same size
and they are measuring by diameter, radius, and circumfrence
When computing the standard deviation, does it matter whether the data are sample data or data comprising the entire population? Explain. Yes. The formula for s is divided by n, while the formula for σ is divided by N − 1. Yes. The formula for s is divided by n − 1, while the formula for σ is divided by N. No. The formula for both s and σ is divided by n − 1. No. The formula for both s and σ is divided by N.
Answer:
Yes. When computing the sample standard deviation, divide by n −1. When computing the population standard deviation, divide by N
Step-by-step explanation:
Sandra spotted the sailboat from the shore and measured the angle from the waterline to the top of the boats mast to be 7° if the top of the mask is 23 feet above the water how far is the middle of the sailboat from the shore? Estimate your answer to the nearest tenth.
Answer:
The middle of the sailboat is approximately 268.8 feet from the shore.
Step-by-step explanation:
Let the distance from shore to the middle of the boat be represented by x, the angle of elevation of Sandra from the shore to the top of the boat mast is 7°. Applying the required trigonometric function to this question, we have;
Tan θ = [tex]\frac{opposite}{adjacent}[/tex]
Tan 7° = [tex]\frac{23}{x}[/tex]
⇒ x = [tex]\frac{23}{Tan 7^{0} }[/tex]
= [tex]\frac{23}{0.12279}[/tex]
= 268.7515
∴ x = 268.8 feet
The middle of the sailboat is approximately 268.8 feet from the shore.
Which statement correctly compares
1–201 and
1512
ol-201 = 151
ol-201 < 51
l-201 > 151
Answer:
Option B.
Step-by-step explanation:
Consider the correct question is "Which statement correctly compares
1. -201 and 151
-201 = 151
-201 < 51
-201 > 151"
The given numbers are -201 and 151. We need to compare these numbers.
We know that all negative numbers are less than positive numbers.
So,
-201 < 151
If both numbers are negative, then the larger negative number is the smaller number.
Therefore, the correct option is B.
What is the value of this expression? (the best answer receives a brainiest)
Answer:
answer is D
Step-by-step explanation:
2^4=16
16+(16-12)=20
over
(6+9)/(7-4)
15/3=5
so the new equation is 20/5=4
Answer:
D. 4
Step-by-step explanation:
Order of Operations: BPEMDAS
Step 1: Exponents
[tex]\frac{16 + (16 -3(4))}{(6+9)/(7-4)}[/tex]
Step 2: Parenthesis
[tex]\frac{16 + (16 -12)}{15/3}[/tex]
Step 3: Parenthesis
[tex]\frac{16 + 4}{15/3}[/tex]
Step 4: Divide
[tex]\frac{16 + 4}{5}[/tex]
Step 5: Add
[tex]\frac{20}{5}[/tex]
Step 6: Divide
4
Solve for h. 3/7=h/14-2/7
Answer:
h = 10
Step-by-step explanation:
Given
[tex]\frac{3}{7}[/tex] = [tex]\frac{h}{14}[/tex] - [tex]\frac{2}{7}[/tex]
Multiply through by 14 to clear the fractions
6 = h - 4 ( add 4 to both sides )
10 = h
Answer:
10
Step-by-step explanation:
We start out with 3/7 = h/14 - 2/7
add 2/7 to both sides:
(5/7) = h/14
Multiply both sides by 14 to get rid of the fraction:
h = 10
A pair of parallel lines intersected by a transversal and forms same side interior angles that are in a 5:1 ratio. what are the measures of two same side interior angles?
Answer:
1st side: 150
2nd side: 30
when a 200 g solution A and 400g of saline solution B are mixed a 6% salt solution is created also when a 400g of saline solution A and 200g of solution B are mixed 7% salt is created find what percent concentration of saline and saline b solution are
Answer:
A = 8%, B = 5%
Step-by-step explanation:
Let
a=concentration of solution A (in percent)
b=concentration of solution B (in percent)
Given
2a+4b = 0.06*(2+4) ...........(1)
4a+2b = 0.07*(4+2) ...........(2)
2(1) - (2)
4a-4a +8b-2b = 6 (2*0.06-0.07)
6b = 6(0.05)
b = 0.05 .............(3)
Substitute (3) into (1) and solve for a
2a+4(0.05) = 0.36
2a = 0.16
a = 0.08
A power failure on the bridge of a Great Lakes freighter has resulted in the ship's navigator having to do her own calculations. She measures the angle between the ship's course and a lighthouse on shore as 32°. After the ship has travelled 1500 m, she measures the angle to be 72°. Determine if the ship was closer to or farther from the lighthouse at the second sighting, and by what distance. (4 marks)
It is impossible to measure the length of a particular swamp directly. Kendra put a stake in the ground and measured from the stake to opposite ends of the swamp, the results being 410 m and 805 m. She measured the angle between the distances to be 57°. What is the length of the swamp? (4 marks)
Answer:
1) The ship is closer
2) 675.73 m
Step-by-step explanation:
1) The given parameters are;
The initial angle between the ship's course and the lighthouse = 32°
The final angle between the ship's course and the lighthouse = 72°
The distance traveled by the sip between he two positions = 1500 m
Therefore we have a triangle formed between the distance covered by the ship and the two distances of the ship from the lighthouse, a and b
Where;
a = The initial distance fro the lighthouse
b = The final distance fro the lighthouse
The angles of the triangle are
32°, (180 - 72) = 108° and 180 - 32 - 108 = 40°
By sine rule we have;
1500/(sin(40)) = a/(sin(108)) = b/(sin(32)) =
Therefore, a = sin(108°) × 1500/(sin(40°)) = 2219.37 m
b = (sin(32°)) × 1500/(sin(40°)) = 1236.61 m
Therefore, a > b
The initial distance fro the lighthouse > The final distance fro the lighthouse, which shows that the ship is closer
2) By cosine rule we have
a² = b² + c² - 2× b×c×cos(A)
Where the given measurements by Kendra are;
410 m and 805 m with an included (in between) angle of 57°, we have;
Let b = 410 m, c = 805 m, and A = 57°, we have;
a² = 410^2 + 805^2 - 2× 410×805×cos(57 degrees) = 456608.77 m²
a = The length of the stream = 675.73 m.
ALGEBRAIC EXPRESSION 11. Subtract the sum of 13x – 4y + 7z and – 6z + 6x + 3y from the sum of 6x – 4y – 4z and 2x + 4y – 7. 12. From the sum of x 2+ 3y 2 − 6xy, 2x 2 − y 2 + 8xy, y 2 + 8 and x 2 − 3xy subtract −3x 2 + 4y 2 – xy + x – y + 3. 13. What should be subtracted from x 2 – xy + y 2 – x + y + 3 to obtain −x 2+ 3y 2− 4xy + 1? 14. What should be added to xy – 3yz + 4zx to get 4xy – 3zx + 4yz + 7? 15. How much is x 2 − 2xy + 3y 2 less than 2x 2 − 3y 2 + xy?
Answer:
Explained below.
Step-by-step explanation:
(11)
Subtract the sum of (13x - 4y + 7z) and (- 6z + 6x + 3y) from the sum of (6x - 4y - 4z) and (2x + 4y - 7z).
[tex][(6x - 4y - 4z) +(2x + 4y - 7z)]-[(13x - 4y + 7z) + (- 6z + 6x + 3y) ]\\=[6x-4y-4z+2x+4y-7z]-[13x-4y+7z-6z+6x+3y]\\=6x-4y-4z+2x+4y-7z-13x+4y-7z+6z-6x-3y\\=(6x+2x-13x-6x)+(4y-4y+4y-3y)-(4z+7z+7z-6z)\\=-11x+y-12z[/tex]
Thus, the final expression is (-11x + y - 12z).
(12)
From the sum of (x² + 3y² - 6xy), (2x² - y² + 8xy), (y² + 8) and (x² - 3xy) subtract (-3x² + 4y² - xy + x - y + 3).
[tex][(x^{2} + 3y^{2} - 6xy)+(2x^{2} - y^{2} + 8xy)+(y^{2} + 8)+(x^{2} - 3xy)] - [-3x^{2} + 4y^{2} - xy + x - y + 3]\\=[x^{2} + 3y^{2} - 6xy+2x^{2} - y^{2} + 8xy+y^{2} + 8+x^{2} - 3xy]- [-3x^{2} + 4y^{2} - xy + x - y + 3]\\=[4x^{2}+3y^{2}-xy+8]-[-3x^{2} + 4y^{2} - xy + x - y + 3]\\=4x^{2}+3y^{2}-xy+8+3x^{2}-4y^{2}+xy-x+y-3\\=7x^{2}-y^{2}-x+y+5[/tex]
Thus, the final expression is (7x² - y² - x + y + 5).
(13)
What should be subtracted from (x² – xy + y² – x + y + 3) to obtain (-x²+ 3y²- 4xy + 1)?
[tex]A=(x^{2} - xy + y^{2} - x + y + 3) - (-x^{2}+ 3y^{2}- 4xy + 1)\\=x^{2} - xy + y^{2} - x + y + 3 +x^{2}- 3y^{2}+ 4xy -1\\=2x^{2}-2y^{2}+3xy-x+y+2[/tex]
Thus, the expression is (2x² - 2y² + 3xy - x + y + 2).
(14)
What should be added to (xy – 3yz + 4zx) to get (4xy – 3zx + 4yz + 7)?
[tex]A=(4xy-3zx + 4yz + 7)-(xy - 3yz + 4zx) \\=4xy-3zx + 4yz + 7 -xy + 3yz - 4zx\\=3xy-7zx+7yz+7[/tex]
Thus, the expression is (3xy - 7zx + 7yz + 7).
(15)
How much is (x² − 2xy + 3y²) less than (2x² − 3y² + xy)?
[tex]A=(2x^{2} - 3y^{2} + xy)-(x^{2} - 2xy + 3y^{2})\\=2x^{2} - 3y^{2} + xy-x^{2} + 2xy - 3y^{2}\\=x^{2}-6y^{2}+3xy[/tex]
Thus, the expression is (x² - 6y² + 3xy).
Autumn runs a farm stand that sells peaches and grapes. Each pound of peaches sells
for $2 and each pound of grapes sells for $4. Autumn sold 35 more pounds of grapes
than pounds of peaches and made $200 altogether. Graphically solve a system of
equations in order to determine the number of pounds of peaches sold, 2, and the
number of pounds of grapes sold, y.
Answer:
She sold 10 pounds of peaches and 45pounds of grapes
Step-by-step explanation:
X= pounds of peaches
x+35=pounds of grapes
2x+4(x+35)=200
2x+4x+140=200
6x=200-140
6x=60
x=10
She sold 10 pounds of peaches and 45pounds of grapes. (Sorry, can’t help you graph it.)
A traveler explores the regions of Mexico. She travels from Sonora to Colima, and
Colima to Tamaulipas. Write two inequalities that represent the two possible distances
from Tamaulipas back to Sonora.
Answer:
809mi
Step-by-step explanation:
There are two ways to travel form Tamaulipas to Sorona. The first if the direct route from Sorona to Tamaulipas which is 809mi. The another route is to travel to Colima from Sorona and then travel to Tamaulipas from Colima. This is the long distance routes in which there are two destination points. The direct route is shorter in length therefore preferable.
Diagram shows helicopter H flying towards an island P
When the helicopter is 100 m above sea level, the pilot sees a man fishing from boat Q. Given the angles of depression of the island P and boat Q from H are 22° and 61.5° respectively.
Calculate the distance, in M, of PQ
Please help me to explain :(
Answer:
193.21 m
Step-by-step explanation:
make a vertical line down from the helicopter that is 100m
tan 61.5 = 100/x x = 54.3 (distance from the point directly below helicopter to boat)
tan 22 = 100/x x = 247.51 (distance from the point directly below helicopter to the island
247.51 - 54.3 = 193.21 (distance from boat to island)
Jonah will cover a cube in wrapping paper. Each edge of the cube is 25 cm long. What is the least amount of
wrapping paper he needs to cover the cube?
15 625 square centimeters
25 square centimeters
37.5 square centimeters
42 25 square centimeters
Save and Exit
Next
Subm
MO
Answer:
3750 cm²
Step-by-step explanation:
To find the answer, we need to find the surface area of the cube. The surface area formula for a cube is 6a² where a = the length of an edge. We know that a = 25 so the surface area is 6 * 25² = 6 * 625 = 3750 cm².
Answer:
37.5 hopefully this is the answer you were looking for!
Step-by-step explanation:
What is the solution set to the inequality?
Answer:
Option (2)
Step-by-step explanation:
To find the solution set of the given inequality we will follow the following steps.
1). Convert the inequality into an equation.
2). Find the solutions from the equation.
3). Check these solutions and intervals on a number line.
Given inequality is 5(x - 2)(x + 4) > 0
Step 1. Equation for given inequality is,
5(x - 2)(x + 4) = 0
Step 2. Solutions for the given equation will be,
(x - 2) = 0 ⇒ x = 2
(x + 4) = 0 ⇒ x = -4
Step 3. Therefore, there will be two critical points on the number line,
x = 2, x = -4
Now we will check the solutions of the given inequality in the given intervals,
x < -4, -4 < x < 2 and x > 2
For x < -4,
Let the solution is x = -5
5(x + 4)(x - 2) = 5(-5 + 4)(-4 - 2)
= 30 > 0
Therefore, x < -4 will be the solution area of the inequality.
For -4 < x < 2,
Let the solution is x = 0
5(x + 4)(x - 2) = 5(0 + 4)(0 - 2)
= -40 < 0
Therefore, -4 < x < 2 will not be the solution set for the given inequality.
For x > 2,
Let the solution is x = 3
5(x + 4)(x - 2) = 5(3 + 4)(3 - 2)
= 35 > 0
Therefore, x > 2 will be the solution area of the inequality.
Summarizing all steps we find that the solution set of the inequality is,
{x | x < -4 Or x > 2}
Option (2) will be the answer.
The fuel efficiency of one type of car is recorded in a scatterplot where the amount of gas used, x (in gallons), is paired with the distance traveled, y (in miles), for various trips. The equation for the line of best fit for the data is y = 28x. How can the y-intercept and slope of this line be interpreted
Answer:
The answer can be interpreted by the distance moved by each gallon :))
Step-by-step explanation:
Answer:
D.
Step-by-step explanation:
Just took it. Edg 2020. Hope this helps :)
You have been saving $12 each week for many weeks. One day, you decide to count your savings and find that you have $384. Write and solve a multiplication equation to find how many weeks w you have been saving.
Answer:
Hope I helped! Brainleist!
Step-by-step explanation:
you get $12/week
and you have $
your equation is
y=12x
now...
y = 384
so
384=12x
x= 32
Ramona works in a clothing store where she earns a base salary of $140 per day plus 14% of her daily sales. She sold $600 in clothing on Saturday and $1200 in clothing on Sunday. How much did she earn over the two days? A. $252 B. $291 C. $392 D. $532
Answer:
I hope this helps!
Answer D
Step-by-step explanation:
Step-by-step explanation:
salary per day =$140
bonus on sales =14%
sales on Saturday =$600
bonus on Saturday sales=14/100*$600
=$84
sales on Sunday =$1200
bonus on Sunday sales=14/100*$1200
=$168
total amount she earned over the two days=$140+$84+$168
=$532
The function gx) = x^2is transformed to obtain function hr.
h(x) = g(x-3).
Which statement describes how the graph of h is different from the graph of g?
A. The graph of his the graph of g vertically shifted down 3 units.
B. The graph of his the graph of ghorizontally shifted left 3 units.
C. The graph of h is the graph of g vertically shifted up 3 units.
D. The graph of h is the graph of g horizontally shifted right 3 units.
the graph will shift 3 units to the right
I NEED HELP ON THIS QUESTION!!!!! I WILL GIVE BRAINLIEST TO THE BEST ANSWER!!!!
Answer:
D
Step-by-step explanation:
Both are exponential decay.
Answer:
D.Step-by-step explanation:
f(0) = 24, f(1) = 6 and f(2) = 0 means f(x) > 0 in (0,2)
and f(0) > f(1) > f(2) means f is decreasing in (0,2)
g(0) = 15 and g(2) = 0 means g(x) > 0 in (0,2)
and g(0) > g(2) means g is decreasing in (0,2)
I NEED HELP PLEASE I GIVE 5 STARS !
Answer:
C. 2[tex]\sqrt{29}[/tex]
Step-by-step explanation:
Square root of 116 is 10.7703296
Square root of 29 is 5.38516481, but as it is multiplied by 2, it becomes 10.7703296
Show that the equations x^2-7x+6=0 and y^2-14y+40=0 form a rectangle.Also find the joint equations of diagonals.
Answer:
1) The region between the four lines x = 6, x = 1, y = 4 and y = 10 describing both equations is a rectangle
2) The joint equations of diagonals are;
5·y = 56 - 6·x and 5·y = 6·x + 14.
Step-by-step explanation:
The equations are;
x² - 7·x + 6 = 0......................(1)
y² - 14·y + 40 = 0.................(2)
Factorizing equation (1) and equation (2) , we get
x² - 7·x + 6 = (x - 6)·(x - 1) = 0
Which are vertical lines at points x = 6 and x = 1
For equation (2) , we get
y² - 14·y + 40 = (y - 10)·(y - 4) = 0
Which are horizontal lines at point y = 4 and y = 10
The region between the four lines x = 6, x = 1, y = 4 and y = 10 describing both equations is a rectangle
2) The points of intersection of the equations are;
(1, 4), (1, 10), (6, 4), and (6, 10)
The end point of the diagonals are;
(1, 10), (6, 4) and (1, 4), (6, 10)
The slope of the diagonals are;
(10 - 4)/(1 - 6) = -6/5 and (4 - 10)/(1 - 6) = 6/5
The equation of one of the diagonals are then, y - 10 = -6/5×(x - 1)
y = -6/5·x + 6/5 + 10 = -6/5·x + 56/5
5·y = 56 - 6·x
The other diagonal is therefore;
y - 4 = 6/5×(x - 1)
y = 6/5·x - 6/5 + 4 = 6/5·x + 14/5
5·y = 6·x + 14.
The joint equations of diagonals are therefore;
5·y = 56 - 6·x and 5·y = 6·x + 14.
If 2x+5=8x, then 12x=?
Answer:
[tex]\boxed{10}[/tex]
Step-by-step explanation:
[tex]2x+5=8x[/tex]
[tex]\sf Subtract \ 8x \ from \ both \ sides.[/tex]
[tex]2x+5-8x=8x-8x[/tex]
[tex]-6x+5=0[/tex]
[tex]\sf Subtract \ 5 \ from \ both \ sides.[/tex]
[tex]-6x+5-5=0-5[/tex]
[tex]-6x=-5[/tex]
[tex]\sf Divide \ both \ sides \ by \ -6.[/tex]
[tex]\displaystyle \frac{-6x}{-6} =\frac{-5}{-6}[/tex]
[tex]\displaystyle x =\frac{5}{6}[/tex]
[tex]\sf Evaluate \ 12x.[/tex]
[tex]\displaystyle 12 \cdot \frac{5}{6} =\frac{60}{6} =10[/tex]
Answer:
10
Step-by-step explanation:
2x+5=8x: First, you are going to subtract 2x from both sides of the equation.
5=6x: Now divide 6x from each side of the equation.
x=5/6: now plug in 5/6 by multiplying this number by 12.
Your final answer should be 10.
Evaluate the expression 5^-2
Answer:
[tex]\boxed{\frac{1}{25} \text { OR } 0.04}}[/tex]
Step-by-step explanation:
[tex]5^{-2}\\\\\text {Apply Negative Exponent Rule: } a^{-b}=\frac{1}{a^b}\\\\5^{-2}=\frac{1}{5^2}=\boxed{{\frac{1}{25}} \text { OR } 0.04}[/tex]
Does someone know how to solve this?
Answer:
6 quarts
Step-by-step explanation:
8 bags
--------
2 quarts
Multiply top and bottom by 3
8*3 bags
--------
2*3 quarts
24 bags
--------------
6 quarts
Answer:
6
Step-by-step explanation:
2 quarts of iced tea = 8 tea bags.
x quarts of Iced tea = 24 tea bags
=> 2/8 = x/24
=> Multiply the extremes and means
=> 8x = 48
=> 8x / 8 = 48 / 8
=> x = 6
6 quarts of iced tea can be made with 24 tea bags.
land and sea corporation has just purchased some shoreline property, and according to their calculations it will cost 2.5 times as much to develop the land as much as it did to buy it. If land and sea believe it will end up spending a combined total of $13,457,500 on both the land and its developments, how much must be the land alone have cost?
Answer:
5,383,000 / *improvments cost 8,074,500
Step-by-step explanation:
if 2.5 is by 'times' then,
13,457,500 / 2.5 =
5,383,000
Which means the cost of the land is 5,383,000
To check just multiply:
5,383,000 x 2.5 = 13,457,500
*Extra
13,457,500 - 5,383,000
= the cost of improvements = 8,074,500
Hope this helps, and have a good day :)
Answer:
$3,845,000
Step-by-step explanation:
Land cost = lDevelopment cost = dTotal cost = $13,457,500As per given:
d= 2.5 lThen total is:
l+2.5l= 134575003.5l= 13457500l= 13457500/3.5l= $3845000Cost of the land alone is $3,845,000
Peter attempted to use the divide-center method to find the line of best fit on a scatterplot.
What was his mistake?
He had a different number of points to the left of the vertical line than to the right of the vertical line.
He had a different number of points above the line of best fit than below the line of best fit.
He didn’t approximate the center of the cluster located on the left side of the vertical line and of the cluster located on the right side of the vertical line.
He didn’t connect the centers of the clusters on the left side and right side of the vertical line to produce the line of best fit.
Answer:
He had a different number of points to the left of the vertical line than to the right of the vertical line.
Step-by-step explanation:
Divide-center method is the method which involves dividing the data on the graph into two equal parts and then fin the line of best fit. The center of each group is approximated and then a line is constructed between two centers which is estimated as line of best fit.
PLEASE HELP ASAP THANKS!!!!!!!!
Answer:
x-√x -12
Step-by-step explanation:
(√x +3)(√x -4)=
x-√x -12
Answer:
the answer is C
Step-by-step explanation:
I used PEMDAS and school knowledge that I learned 2 years ago that I can't explain much, cause I i am bad at math, most of the time