The composition of the earth's atmosphere during prehistoric times can be measured from trapped bubbles.Nitrogen measurements were made on 32 samples with a mean of 71 and a sample standard deviation of 5.

If today's atmosphere's nitrogen content is 78, state a null and alternate hypothesis concerning changes in the earth's atmosphere.

Ho:

Ha:

Which test would you use to evaluate this study?

Test your hypothesis by selecting an a level:

Test and report your P-value

What conclusions did you reach?

Do you have any issues with the t test?