Answer:
0.9812
Explanation:
Given that human weights are normally distributed with mean 175 and standard deviation 36 pounds
For a sample of 9 people std error of sample would be

Thus we find that sample mean is N(175, 12)
The plane will lift safely if sample average <200 pounds
i.e. Probability that it can safely lift off (i.e., the average weight of a person in the helicopter is less than 200)
=

~0.981