The symbol is often used to denote the area under the standard normal curve that lies

The symbol ɸ is often used to denote the area under the standard normal curve that lies to the left of a specified value of z. Consider a one-mean z-test. Denote z0 as the observed value of the test statistic z. Express the P-value of the hypothesis test in terms of if the test is
a. Left tailed.
b. Right tailed.
c. Two tailed.