Find slope of a line perpendicular to each given

Jose bought 20 shares of netflix at the close price of $117.98. in a few years, jose sells all of his shares at $128.34. how much money did jose make? a.) $192.50 b.) $207.20 c.) $212.50 d.) $224.60

What is the radius of a circle with an area of 78.5 cubic inches? use 3.14 for pie

At store a, erasers are sold individually. the cost y of x erasers is represented by the equation y=0.75x. the costs of erasers at store b are shown in the graph.