Probability and Statistics assistance needed! Story Problem:
The average salary of doctors in a certain region is $85,000 with a standard deviation of $10,000.

*using the given mean and standard deviation*

Questions:

1) What is the probability of randomly choosing a doctor whose salary is at least $65,000?

2) What is the probability of randomly choosing a doctor whose salary is between $75,000 and $95,000?

3) What is the probability of randomly choosing a doctor whose salary is greater than or equal to $105,000?

I would greatly appreciate it if someone could show their work and how they got their answer so I can learn. Thank you!