Answer:
The answer is : b) a confound
Step-by-step explanation:
While manipulating, is possible that some factors like noise in the hall, can affect learning in one of the groups but not in the other.
This possibility reflects the presence of a confound.
We can define a confounding variable as an external influencing factor which results in bringing changes in the effects of a dependent and independent variable.
This variable changes the outcome of an experiment and produces useless results.
Answer:
The answer is 24
Step-by-step explanation:
24/4 is 6 and then you add 6 to 3 which is 9
Answer:
Step-by-step explanation:
Represent the length of one side of the base be s and the height by h. Then the volume of the box is V = s^2*h; this is to be maximized.
The constraints are as follows: 2s + h = 114 in. Solving for h, we get 114 - 2s = h.
Substituting 114 - 2s for h in the volume formula, we obtain:
V = s^2*(114 - 2s), or V = 114s^2 - 2s^3, or V = 2*(s^2)(57 - s)
This is to be maximized. To accomplish this, find the first derivative of this formula for V, set the result equal to 0 and solve for s:
dV
----- = 2[(s^2)(-1) + (57 - s)(2s)] = 0 = 2s^2(-1) + 114s - 2s^2
ds
Simplifying this, we get dV/ds = -4s^2 + 114s = 0. Then either s = 28.5 or s = 0.
Then the area of the base is 28.5^2 in^2 and the height is 114 - 2(28.5) = 57 in
and the volume is V = s^2(h) = 46,298.25 in^3
