Free points cuz im bored

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?

If f(x)=2x-6 and g(x)=3x+9, find (f-g)(x)

The quadratic function h(t)=-16.1t^2+150 choose the graph representation