The cost of buying x ornaments at $4.25 an ornament.?

A. Proportional
B. Non Proportional

Really need on these. i have no idea what to do

Me complete this proof! prove that a quadrilateral is a square. me with the steps for this proof.

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