In which of the following situations should the t distribution be used? a. When the sample standard deviation is used to estimate the population standard deviation b. Only when the population mean is 0 c. When the sample size is less than 30 d. When the population is not normally distributed

a. When the sample standard deviation is used to estimate the population standard deviation

Step-by-step explanation:

T or Z distribution:

If we have the standard deviation for the sample, we use the t-distribution.

If we have the standard deviation for the population, we use the z-distribution.

Thus, the correct answer for this question is given by option a.

Wages she earn = £124.1

Step-by-step explanation:

Given:

Number of hour work in June = 17 hour

Rate = £7.30 per hour

Find:

Wages she earn

Computation:

Wages she earn = Number of hour work in June x Rate

Wages she earn = 17 x £7.30

Wages she earn = £124.1