Answer:
C. 5 weeks.
Step-by-step explanation:
In this question we have a random variable that is equal to the sum of two normal-distributed random variables.
If we have two random variables X and Y, both normally distributed, the sum will have this properties:

To calculate the expected weeks that the donation exceeds $120, first we can calculate the probability of S>120:

The expected weeks can be calculated as the product of the number of weeks in the year (52) and this probability:

The nearest answer is C. 5 weeks.
Answer: It would be B 9/50
Step-by-step explanation: if you take 3/7 and x it by 0.1 you get 0.04285714285 and then if you divide that by 5/21 you get 0.18 which equals 9/50 as a fraction