Write the inequality that describes the graph? I don’t know how to figure out the problem help plz

Multiplying an even number of negative numbers gives an answer that is choose from:

If f(x)=-x^2+6x-1 and g(x)=3x^2-4x-1,find(f+g)(x)

Weekly wages at a certain factory are normally distributed with a mean of $400 and a standard deviation of $50. find the probability that a worker selected at random makes between $450 and $500