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3 years ago

11

when a study is designed so that neither the subjects nor the experimenters know which subjects are in the treatment group and w

hich ones are in the control group, the study is called a ____ experiment.

2 answers:

Nata [24]3 years ago

5 0

(taken from a source)

<span>double blind
</span>
Hope this helped!

:)

Greeley [361]3 years ago

3 0

Answer:double-blind (APEX)

Step-by-step explanation:

You might be interested in

85.87 J or heat energy is added to a 34.8 g mass of substance the temperature rises from 21.76°C

Andru [333]

Answer:

The required specific heat is 196.94 joule per kg per °C

Step-by-step explanation:

Given as :

The heat generated = Q = 85.87 J

Mass of substance (m)= 34.8 gram = 0.0348 kg

Change in temperature = T2 - T1 = 34.29°C - 21.76°C = 12.53°C

Let the specific heat = S

Now we know that

Heat = Mass × specific heat × change in temperature

Or, Q = msΔt

Or, 85.87 = (0.0348 kg ) × S × 12.53°C

Or , 85.87 = 0.4360 × S

Or, S = $\frac{85.87}{0.4360}$

∴ S = 196.94 joule per kg per °C

Hence the required specific heat is 196.94 joule per kg per °C Answer

7 0

2 years ago

Light travels 1.08 x 10 9 kilometers in one hour. How far does it travel in 2 hours?

ozzi

The distance traveled by the light in 2 hours is 2.16×10⁹ km.

<h3 /><h3>Distance:</h3>

This is the total length of space between two points covered by an object. Distance has no regard for direction as it is termed a scalar quantity. The S.I unit of distance is meter(m).

To calculate the distance traveled by the light in 2 hours, first, we need to calculate the speed of the light.

Formula:

S = d/t................. equation 1

Where:

S = speed
d = distance travelled

t = time

From the question,

Given:

d = 1.08×10⁹ km
t = 1 hour

Therefore,

s = 1.08×10⁹/1

s = 1.08×10⁹ km/h

The distance traveled in 2 hours is

d = 2×1.08×10⁹
d = 2.16×10⁹ km

Hence, the distance traveled by the light in 2 hours is 2.16×10⁹ km

Learn more about distance here: brainly.com/question/23848540

6 0

2 years ago

Left parenthesis 5 plus 2 square root of 6 right parenthesis squared = a plus b square root of 6 then the value of a and b are

Ganezh [65]

Answer:

The values of $a$ and $b$ are $33$ and $\frac{20\sqrt{3}}{3}$ , respectively.

Step-by-step explanation:

The statement is equivalent to the following mathematic expression:

$\left(5 + 2\sqrt{2})^{2} = a + b\cdot \sqrt{6}$ (1)

By definition of the perfect square trinomial:

$25 + 20\cdot \sqrt{2} + 8 = a + b\cdot \sqrt{6}$

$33 + 20\sqrt{2} = a + b\cdot \sqrt{6}$

And by direct comparison we have the following system:

$a = 33$ (2)

$b\cdot \sqrt{6} = 20\sqrt{2}$ (3)

By (3), we solve for $b$ :

$b = \frac{20}{\sqrt{3}}$

$b = \frac{20\sqrt{3}}{3}$

The values of $a$ and $b$ are $33$ and $\frac{20\sqrt{3}}{3}$ , respectively.

6 0

2 years ago

Point A is at (-5, -4) and point M is at (0, -3.5).

ludmilkaskok [199]

Answer:

The coordinates of point B are (5,-3)

Step-by-step explanation:

we know that

The formula to calculate the midpoint between two points is equal to

$M=(\frac{x_1+x_2}{2},\frac{y_1+y_2}{2})$

In this problem

Point A is at (-5, -4) and point M is at (0, -3.5)

$point\ A=(x_1,y_1)\\point\ B=(x_2,y_2)\\point\ M=(0,-3.5)$

substitute in the formula

$(0,-3.5)=(\frac{-5+x_2}{2},\frac{-4+y_2}{2})$

so

Solve for x_2

$0=\frac{-5+x2}{2}\\x_2=5$

Solve for y_2

$-3.5=\frac{-4+y_2}{2}\\-7=-4+y_2\\y_2=-3$

therefore

The coordinates of point B are (5,-3)

7 0

3 years ago

Read 2 more answers

Find the length of each segment with endpoints A and B. Select the exact answer. (This means that it is either an integer or in

kondaur [170]

It’s b bucko I did that

4 0

3 years ago