Complete parts (a) through (c) below.

(a) Determine the critical value(s) for a right-tailed test of a population mean at the α=0.10 level of significance with 15 degrees of freedom.

(b) Determine the critical value(s) for a left-tailed test of a population mean at the α=0.01 level of significance based on a sample size of n=10.

(c) Determine the critical value(s) for a two-tailed test of a population mean at the α=0.01 level of significance based on a sample size of n=12.

(a) t crit= _________(Round to three decimal places as needed.)

(b) t {Subscript crit}= _________ (Round to three decimal places as needed.)

(c) t {Subscript crit}= _________( Round to three decimal places as needed.)