The compressive strength of samples of cement can be modeled by a normal distribution with a mean

Question:

The compressive strength of samples of cement can be modeled by a normal with a mean of 6000 kilograms per square centimeter and a standard deviation of 100 kilograms per square centimeter.
(a) What is the probability that a sample’s strength is less than 6250 Kg/cm2?
(b) What is the probability that a sample’s strength is between 5800 and 5900 Kg/cm2?
(c) What strength is exceeded by 95% of the samples?
Distribution
The word "distribution" has several meanings in the financial world, most of them pertaining to the payment of assets from a fund, account, or individual security to an investor or beneficiary. Retirement account distributions are among the most...