Tests show that the pressure, in pounds per square inch (Psi) required to break skate boards is normally distributed with a mean of 54.7 and standard deviation of 6.2

a)what is the probability that a board will require at least a pressure of 70 to break?
b)64% of skateboards can only withstand less than a certain amount of pressure. What is that pressure?
Thanks in advance.

See the webpage I gave you in your other post