A random variable is normally distributed with a mean of

A random variable is normally distributed with a mean of 25 and a standard deviation of 5. If an observation is randomly selected from the distribution,
a. What value will be exceeded 10% of the time?
b. What value will be exceeded 85% of the time?
c. Determine two values of which the smallest has 25% of the values below it and the largest has 25% of the values above it.
d. What value will 15% of the observations be below?