The average monthly mortgage payment including principal and interest is $982 in the United States. If the standard deviation is approximately $180 and the mortgage payments are approximately normally...

The average monthly mortgage payment including principal and interest
is $982 in the United States. If the standard deviation is approximately $180 and the
mortgage payments are approximately normally distributed, find the probability that a
randomly selected monthly payment is
a. Greater than $1000.
b. Between $800 and $1150