Question 1158634
Random sample and other assumptions assumed
Ho: salary if $40000
Ha: it is not
alpha=0.05 p{reject Ho|Ho true}
test stat is a z=(xbar-mean)/sigma/sqrt(n)
reject if |z|>1.96
=(3228)/4000/sqrt(20)
z=3.61
reject Ho p-value<0.0004
the reported salary is not $40,000