A friend of mine studies the effects of praise on happiness

A friend of mine studies the effects of praise on happiness. She believes that children who receive praise are happier overall than children who do not receive praise. She measures happiness by counting the number of times a child smiles in a one hour period. She knows that in the population of children who do not receive praise smiles average 4 times per hour with a standard deviation of .5, and that these data are normally distributed. She selects a sample of 100 children whom she knows receive praise and finds that they smile an average of 3.5 times per hour. The characteristics of the appropriate comparison (sampling) distribution are

a mean of zero and a standard deviation of 1.

a mean of 4 and a standard deviation of .5.

a mean of 4 and a standard deviation of .05.

a mean of 3.5 and a standard deviation of .5.

A distribution of sample means is a collection of sample means from?

samples of different sizes from different populations.

samples of size N from different populations.

samples of size N from the same population.

samples of different sizes from the same population

Solution