This Instructional Activity is a part of the Lesson 4, Unit 5, Grade 8. Practice the definitions with this example. Classify each of the functions described below as either discrete or not discrete: The function that assigns to each whole number the cost of buying that many cans of beans in a particular grocery store, The function that assigns to each time of day one Wednesday the temperature of Sammy's fever at that time, The function that assigns to each real number its first digit.