This question is asked on an upcoming homework assignment:
The weekly demand for a product approximately has a normal distribution with mean 1,000 and standard deviation 200. The current on hand inventory is 2,200 and no deliveries will be occurring in the next two weeks. Assuming that the demands in different weeks are independent:
$a)$ What is the probability that the demand in each of the next two weeks is less than 1,100?
$b)$ What is the probabbility that the total of the demands in the next two weeks exceeds 2,200?
I don't even know where to begin.