I'm very stuck right now > .<

Which expression is equivalent to (9x - 3 1/ + 1 3/8)

(if f(x)=4x^2 and g(x)=x+1, find (f o g)(x)

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?