I need help with this geometry review question

Aconvex octagon has interior angles that measures 73 degrees, 172 degrees, 132 degrees, 59 degrees, 154 degrees, 163 degrees, x degrees, 2x degrees find the value of the missing angles

Which of the following expressions is equal to 2x^2+8

Logan wants to know how many skateboards have defective parts. he inspects 20,000 skateboards and keeps track of the number of defects per board. use his probability distribution table to find the expected value for defects on a skateboard.