The mean lactation (nursing) period of all earless seals is 22 days. Grey seals are one of several types of earless seals. A sample of 17 female grey seals had the following lactation periods, in days:

25.1	24.6	24.7	29.2	27.2
24.8	27.3	26.9	29.1	25.2
28.2	26.5	24.8	22.6	20.6
23	30.6

At the 5% significance level, does the data provide sufficient evidence to conclude that mean lactation (nursing) period of grey seals is the same as 22 days? Assume that the population standard deviation is 2.6 days. You may also assume that the sample is from a normal population. (Note: The average and the standard deviation of the data are respectively 25.91 days and 2.59 days.)

Procedure: Select an answer One mean T Hypothesis Test One variance χ² Hypothesis Test One proportion Z Hypothesis Test One mean Z Hypothesis Test

Assumptions: (select everything that applies)