Number 9 thank you ASAP

Rockwell hardness of pins of a certain type is known to have a mean value of 50 and a standard deviation of 1.1. (round your answers to four decimal places.) (a) if the distribution is normal, what is the probability that the sample mean hardness for a random sample of 8 pins is at least 51?

One positive integer is 2 less than another. the product of the two integers is 24. what are the integers?

What are the solutions for the following system? -2x^2+y=-5 y=-3x^2+5