Please answer sub parts The mean age for a person getting married for the first time is 27.3 years. Assume the ages for first marriages are normal with a standard deviation of 4.9 years. (Give...

Please answer sub parts

The mean age for a person getting married for the first time is 27.3 years.  Assume the ages for first marriages are normal with a standard deviation of 4.9 years. (Give probability answers to four decimal places.)

      a) What is the probability that a person being married for the first time is between 21.5 and 30.7 years old?

      b) What is the probability that a person being married for the first time is over 31.3 years old?

      c)  What is the probability that a person being married for the first time is between 23.4 and 31.8 years old?

      d)  85% of people getting married for the first time do so before what age?