The difference between an observational study and an experiment is that:


A. in an observational study, only one group is studied, and in an experiment, two groups are studied.
B. in an observational study, the researchers do not control treatment, and in an experiment, they do.
C. in an experiment, cause-and-effect is analyzed, and in an observational study, it is not.
D. in an experiment, one group is studied over a short period of time, and in an observational study, the group is studied over a longer period of time.

Answer:

-k

Step-by-step explanation:

Cos(140)=cos(180-40)=-cos(40)=-k

Answer:

Step-by-step explanation:

Sin (90 - A)  = Cos A

Cos (90 + A) =   -Sin A

Sin 50 = Sin (90 - 40)

          = Cos 40

         = k

Cos 140 = Cos (90 + 50)

             = - Sin 50

            = (- k)

Answer:

-2 + 6i

Parallelogram

Step-by-step explanation:

( 5 - 2i ) + ( - 7 + 8i )

remove parenthesis

5 - 2i + ( -7 ) + 8i

combine like terms

5 + (-7) = -2

-2i + 8i = 6i

-2 + 6i

The arrows on the opposite sides indicate that the sides are parallel

A shape with two sets of parallel sides is known as a parallelogram

Answer:

The answer to this question is C.

Answer:

Step-by-step explanation:

[tex]\frac{1.107}{123} \times \frac{1.998}{333} = [/tex]

[tex] = > 9 \times 6[/tex]

[tex] = 45[/tex]

Answer:

Step-by-step explanation:

[tex]\frac{1.107}{123}*\frac{1.998}{333}= 0.009 * 0.006 = 0.000054[/tex]

1107÷ 123 = 9

The dividend has 3 decimal places. So, take 3 decimal places from the right towards left in the result  0.009

1.107 ÷ 123 = 0.0009

0.009 * 0.006

First multiply 9 * 6 = 54

Now, count the number of decimal place in the multiplicands. 0.009 has 3 decimal places and 0.006 has 3 decimal places. So totally, 3+ 3 = 6 decimal places in the result

0.009 * 0.006 = 0.000054

Answer:

x=-2/3

Step-by-step explanation:

So let's start off with adding 4x on both sides, we add them to cancel out the -4x on the right hand side.

4x+-9x=-5x

Now, as for the fractions all we really gotta do here is add and subtract them. Let's subtract 5/6 on both sides. once we do that we get:

2/3+7/2-5/6=-5x

A quick trick for adding and subtract fractions is to cross multiply.

2/3+7/2

Multiply 3 times 7 and 2 times 2, then we'll multiply 3 times 2 to get a denominator.

3*2=6 (our denominator)

3*7=21

21/6

2*2=4/6

21/6+4/6=

25/6

Awesome! Now we have two like denominators so we don't have to do any additional cross multiplying. So, we can subtract 25/6-5/6=20/6.

Now, all we're left with is:

20/6=-5x

We can multiply 6 on both sides to isolate the 20.

20=-30x

Divide -30 on both sides!

x=-2/3

Hope this helps!

Answer:

rtyujn

Step-by-step explanation:

er456y7ujm

Proving that quadrilaterals are congruent takes more because all quadrilaterals are polygons of four sides and they all have a sum angle of 360°

A quadrilateral can be defined as a polygon shape that possesses four sides.

Congruent quadrilaterals are those quadrilaterals that are similar in sides and angles.

For example, a parallelogram needs to be proved by both the sides and the angles

In conclusion, Proving that quadrilaterals are congruent takes more because all quadrilaterals are polygons of four sides and they all have a sum angle of 360°

Learn more about Congruent quadrilaterals: https://brainly.com/question/224113

#SPJ1

Answer:

Empty square = +

Empty Circle = ÷

Step-by-step explanation:

In order to eliminate the extra numbers from the equation you have to do the opposite of the problem. So...

-6x-1=5

-6x -1+1 = 5+1 (eliminating the 1 from the -6x side and adding it to the other side)

-6x = 6

-6x ÷ -6 = 6 ÷ -6 ( eliminating the-6 so that one side just has x)

so... x= -1

Answer: Option B is your correct answer.

Answer:

f(2) = 0 and g(2) = 0

f(2) = g(2) TRUE

b) f(0) = 2 and g(0) = -2

f(0) = g(0) FALSE

c) f(2) = 0 and g(0) = -2

f(2) = g(0) FALSE

d) f(0) = 2 and g(2) = 0

f(0) = g(2) FALSE

Step-by-step explanation:

the answer is in the image above

Answer:

a₅₀₀ = 3517

Step-by-step explanation:

a₁ represents the first term and d the common difference

Here a₁ = 24 and d = 31 - 24 = 7 , then

a₅₀₀ = 24 + (499 × 7) = 24 + 3493 = 3517

Answer:

{F, G, H, I, J, K, L, M, N, O, P}

are the points between segment EQ :)

Answer:

Percent * base = Amount

660 g = 660 g

3kg = 3000g

percent(3000) = 660

percent = 660/3000

percent = .22

.22 = 22%

Step-by-step explanation:

Answer:

Growth

Step-by-step explanation:

When x value increase, y value also increase, So growth.

When x = 1   ;f(1) = 2

When x = 2  ; f(2) = 2² = 4

When x = 3  ; f(3) = 2³ = 8

Answer:

Exponential Growth

Step-by-step explanation:

I found this photo that helps differentiate both growth and decay :)

I hope this helps! :)

Answer:

The probability is 32/81

Step-by-step explanation:

We know that:

The probability that the team wins is p = 2/3

Then the probability of not winning is q = 1 - p = 1 - 2/3 = 1/3

The team plays 4 matches.

We want to find the probability that the team wins 1 more than half of the number of matches played.

So if there are 4 matches, the half is 2 matches

one more than half is then 3 matches.

Let's assume that the team wins the first 3 matches, and does not win the last match.

match one, the team wins with prob: P₁ = 2/3

match two, the team wins with prob: P₂ = 2/3

match three, the team wins with prob: P₃ = 2/3

match four, the team wins with prob: P₄ = 1/3

The joint probability is the product of all the individual probabilities:

P = (2/3)*(2/3)*(2/3)*(1/3)

Now we must also considerate the permutations, we have the cases:

the team does not win the fourth match

the team does not win the third match

the team does not win the second match

the team does not win the first match

So we have just four permutations, then the total probability is:

probability = 4*P = 4*(2/3)*(2/3)*(2/3)*(1/3) = 4*(8/81) = (32/81)

Answer:

13

Step-by-step explanation:

-2x + 6 = -20

Step 1 subtract 6 from both sides

6 - 6 cancels out

-20 - 6 = -26

We now have -2x = -26

Step 2 divide both sides by -2

-2x/-2 = x

-26/-2 = 13

We're left with x = 13

Answer:

[tex]A \approx 1.488[/tex]

Step-by-step explanation:

Por definición de razones trigonométricas, tenemos las siguientes identidades:

[tex]\tan \theta = \frac{y}{x} = \sqrt{2}[/tex] (1)

[tex]\sin \theta = \frac{y}{\sqrt{x^{2}+y^{2}}}[/tex] (2)

[tex]\cos \theta = \frac{x}{\sqrt{x^{2}+y^{2}}}[/tex] (3)

Si [tex]\theta[/tex] es agudo, entonces [tex]x, y > 0[/tex].

De (1), suponemos [tex]x = 1[/tex] que [tex]y = \sqrt{2}[/tex], entonces los valores de las funciones seno y coseno:

[tex]\sin \theta = \frac{\sqrt{2}}{\sqrt{5}} = \sqrt{\frac{2}{5} }[/tex]

[tex]\sin \theta = \frac{\sqrt{10}}{5 }[/tex]

[tex]\cos \theta = \sqrt{\frac{1}{5} }[/tex]

[tex]\cos \theta = \frac{\sqrt{5}}{5}[/tex]

Por último, calculemos [tex]A[/tex]:

[tex]A = 3\cdot \left(\frac{\sqrt{10}}{5} + \frac{\sqrt{5}}{5} \right) - \sqrt{7}[/tex]

[tex]A \approx 1.488[/tex]

Answer:

x=-9/10

Step-by-step explanation:

2x+8x+16=7

Step 1: Simplify both sides of the equation.

2x+8x+16=7

(2x+8x)+(16)=7(Combine Like Terms)

10x+16=7

10x+16=7

Step 2: Subtract 16 from both sides.

10x+16−16=7−16

10x=−9

Step 3: Divide both sides by 10.

10x/10

=

−9/10

x=-9/10

Answer:

x = - 4 ± [tex]\sqrt{7}[/tex]

Step-by-step explanation:

Given

x² + 8x + 16 = 7 ( subtract 16 from both sides )

x² + 8x = - 9

Using the method of completing the square

add ( half the coefficient of the x- term)² to both sides

x² + 2(4)x + 16 = - 9 + 16

(x + 4)² = 7 ( take the square root of both sides )

x + 4 = ± [tex]\sqrt{7}[/tex] ( subtract 4 from both sides )

x = - 4 ± [tex]\sqrt{7}[/tex]

Then

solutions are x = - 4 - [tex]\sqrt{7}[/tex] , x = - 4 + [tex]\sqrt{7}[/tex]

Answer:

The answer is E.

Step-by-step explanation:

A quadrilateral that has only one pair of parallel sides is called a Trapezoid.

Answer: UHHHHH i shall halp ya

Step-by-step explanation:

if its 133 in ounces its 293.215 in pounds

Answer: 8 pounds and 5 ounces

Step-by-step explanation: Do 16 ounces divided by 2 and it will give you 8 or do 8 times 2 which will give you sixteen. I prefer you do the other way and then do 10 dividedy2to get 5 ounces. The cop is 2.

Answer:

0.77

Step-by-step explanation:

Given that:

P(A) = 0.64

P(B) = 0.25

P(AnB) = 0.12

Probability that customer buys either pet or baby supplies ; P(AuB)

P(AuB) = P(A) + p(B) - p(Ann)

P(AuB) = 0.64 + 0.25 - 0.12

P(AuB) = 0.77

Answer:

8units

Step-by-step explanation:

area of a triangle=1/2base x height

1/2×4×4

2×4

8units

Answer:

Top right

Step-by-step explanation:

First, we have "h is increasing on the interval (3, +∞)." This means that h must be increasing for all values 3 and higher. This is shown on the top left, top right, and bottom right graphs because when x goes up on each of them, the function increases as well. However, for the bottom left graph, this is not shown because as x goes from 3 to 4, the function decreases.

Next, the statement given is "h(4)=2". This means that when the x value is 4, the y value is equal to 2. This is true for the top left and top right pictures. However, for the bottom right, as the x value is 4 on the x axis, the corresponding y value is 1, not 2.

This leaves us with the top left and top right. The final characteristic given is "The domain of h is [3, +∞). This means that the x values of said function only go from 3 to infinity. As the top left graph has values of x below 3, this leaves the top right graph as h

Answer:

a) The area of the triangle AQB is 43 square centimeters.

b) The length of the line segment AQ is approximately 14.866 centimeters.

Step-by-step explanation:

a) The procedure consist in subtracting the areas of triangles APQ, ASB and BRQ of the area the rectangle, that is to say:

[tex]A = (9\,cm)\cdot (14\,cm) - \frac{1}{2}\cdot (5\,cm)\cdot (14\,cm) - \frac{1}{2}\cdot (8\,cm)\cdot (9\,cm) -\frac{1}{2}\cdot (4\,cm) \cdot (6\,cm)[/tex]

[tex]A = 43\,cm^{2}[/tex]

The area of the triangle AQB is 43 square centimeters.

b) The length of the line segment AQ is determined by Pythagorean Theorem:

[tex]AQ = \sqrt{AP^{2}+PQ^{2}}[/tex] (1)

[tex]AQ = \sqrt{(5\,cm)^{2}+(14\,cm)^{2}}[/tex]

[tex]AQ \approx 14.866\,cm[/tex]

The length of the line segment AQ is approximately 14.866 centimeters.

Answer:

500ml orange juice is the most cost effective

Answer:

Step-by-step explanation:

28 kg + 750 g = 28*1000 + 750

                          28000 + 750

                       = 28750 g

Number of sack = Total quantity of sugar ÷ quantity of sugar in a sack

                           = 28750 ÷ 500

                           =  57 sacks

Answer:

57 sacks

Step-by-step explanation:

28750 ÷ 500 =

57 sacks

Glad to help! :)

Answer:

None Of the Above.

Step-by-step explanation:

As we know that the general equation of circle is

( x - h )^2 + ( y - k )^2 = r^2

putting h=5 and k= 4 and r= 5

x² + 25 - 10x + y² +16 - 8y = 25

x² + y² - 10x - 8y + 16 = 0 is the answer.

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Answer:

24 inches

Step-by-step explanation:

2 yards to inches :

2 x 12 = 24

If my answer is incorrect, pls correct me!

If you like my answer and explanation, mark me as brainliest!

-Chetan K

Answer:

72 inches

Step-by-step explanation:

1 yard = 3 feet

1 foot = 12 inches

1 yard = 3(12) inches or 36"

∴ 2 yards = 72 inches