Aresearcher measures mean health scores of children at a local school and compares these scores to the mean health score known in the general population. assuming that the population variance is unknown, what type of t test is appropriate for this study? a. one-sample t test b. two-independent sample t test c. there is not enough information to answer this question.

b. two-independent sample t test

Step-by-step explanation:

the question stated that the variance is unknown, and standard deviation is paramount for a t test calculation.

the t-value is determined from the relationship

t = (x−µ) s

where x is the mean value of a sample, µ is the mean value of the population from which the sample is drawn,

s is the standard deviation of the sample and

N is the number of independent observations in the sample.

therefore, for independent sample t test, the variance can be calculated from the values of the two mean given with the sample size.

15

step-by-step explanation:

we are given the following expression and we are to solve it and find the product:

-13 × (-5)

solving the given expression in the standard order of solving a mathematical expression, beginning with the opening of brackets and then multiplying the terms and changing their signs.

-3 × -5 = 15 (answer is positive because when negative is multiplied with negative, it gives a positive answer)

7

step-by-step explanation: