### Problem 8 assign 4 RStudio It is known that the IQ scores of people in the United States have a normal distribution with mean 100 and standard devitaion 15.

a) If a person is selected at random, find the probability that the person's IQ score is less than 85. ```{r} #include solution in R ``` b) Jason's IQ score is equal to the 75th percentile. What is his IQ? Round it off to the nearest integer. ```{r} #include solution in R ``` c) What proportion of this population have IQ scores above 120? ```{r} #include solution in R ```