Question 1193684
Ho: mean is >=14.0
Ha: mean is < 14.0
alpha is 0.10 p{reject Ho|Ho true}
test is a t (0.90, df=9)
critical value t<-1.383. mean is 11.05 sd is 6.46
calculation is t=(11.05-14.0)/6.46/ sqrt(10)
=-1.44
reject Ho and conclude there is sufficient evidence to reject Ho and that the claim that the mean lead concentration is less than 14.0 
p-value is 0.09