Pls help with the matching

Leo has b boxes of pencils. each box contains 6 pencils. he has a total of 42 pencils. the equation that represents this situation the value of b that makes the equation true the first one is b+6=42,6b=42,b=42+6,or 42b=6 the second one are 7,836 48

Given f(x)= 9x+1 and g(x)=x^3, choose the expression (f*g)(x)

Which expression converts 45 degree to radians