1. Write a HyperStudio stack with card # 1 containing four buttons labeled Add, Subtract, Multiply, and Divide and use HyperLOGO to implement each of these button commands for two input numbers. Show the design of your command card and a snap of each of the output calculations.
2. Design card # 2 of this stack with a button labled Average which computes the average of an arbitrary number of positive numbers. Terminate the input with a negative "sentinel."