Based on the information given for each of the following studies, decide whether to reject the null hypothesis. ...

  

Based on the information given for each of the following studies, decide whether to reject the null hypothesis. For each, give the Z-score cutoff or cutoffs on the comparison distribution at which the null hypothesis should be rejected, the Z score on the comparison distribution for the sample score, and your conclusion. Assume all populations are normally distributed.

Study A, population mean=100; population standard dev=10; Sample score=80; p<.05; one-tail test with low predicted. ( Please explain. Thank you).

Study B, population mean=100; population standard dev=20; Sample score=80; p<.01; two-tail test.

Study C, population mean=74.3; population standard dev=11.8; Sample score=80; p<.01; two-tail test.

Study D, population mean=16.9; population standard dev=1.2; Sample score=80; p<.05; one-tail test with low predicted.