Please explain the answer and show the calculation:

Intelligence Quotient (IQ) scores are normally distributed with a mean of 100 and a standard

deviation of 15.

Based on the properties of the normal distribution:

1) What proportion of people are expected to have IQ scores between 85 and 115?

2) What is the probability that any of us would have an IQ score of a super-genius, i.e., above 145?

3) 95% of the population will have IQ scores between ....... and ......

Reference:

http://people.umass.edu/biep540w/pdf/Introduction%20to%20the%20NormalDistribution%2029%20slides%20(University%20of%20Sussex).pdf