Two different expressions equivalent to 8d - 4? Please help me i need to have the answer for a test!!

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

Select all expressions that are equivalent to 2(3x + 7y). question 1 options: 6x + 14y 6x + 7y 1(6x + 14y)

Out of 50 students surveyed, 16 have a dog. based on these results, predict how many of the 280 students in the school have a dog.