Please explain and answer the question

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

What’s the answer ? use the picture to see the problem

Deepak plotted these points on the number line. point a: –0.3 point b: – 3 4 point c: – 11 4 point d: –0.7 which point did he plot incorrectly?