Answer:
Step-by-step explanation:
Given that the average annual income of 100 randomly chosen residents of Santa Cruz is $45,221 with a standard deviation of $30,450.
a) Std deviation of mean = 
b) 
Test statistic = Mean diff/std dev of mean = 
p value = 0.043
Since p >0.01 we accept null hypothesis.
c) For two sided p value = 0.086
Here we have

Test statistic = 
p value = 0.3221
Since p >alpha, we accept null hypothesis.