Question 1183486
Assuming random and normal distribution 
this is a one-way one sample t-test
t(0.975,df=4) with critical value of 2.132
t=(xbar-mean)/s/sqrt(n)
mean is 89
t=(89-100)/15.81/sqrt(5)
=11 sqrt(5)/15.81=1.56
insufficient evidence to reject Ho, p-value is 0.097