Internal validity is that: (a) the estimator of the causal effect should be unbiased and consistent.(b) the estimator of the causal effect should be efficient. (c) inferences and conclusions can be generalized from the population to other populations.(d) ols estimation has been used in your statistical package.

The correct answer is option A.

Explanation:

Internal validity is a concept to tell the validity of the statistical analysis, the extent to which it supports the cause and effect relationship.

Inferences here are applicable only on the population on which study is based.

If the inferences can be generalized then we say external validity is there.

Also, for internal validity the estimator of the causal effect should be unbiased and consistent.

start by isolating the variable on one side by adding 43w^2 to both sides.   the equation will read:

25w^2+5=0

*subtract 5 from both sides*

25w^2=-5

*divide both sides by 25*

w^2=-1/5

*take the square root of both sides*

w=√(-1/5)

the square root of -1 is i.   the square root of 5 remains √5

the answer is i/√5.

hope this

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