For each pair of variables determine whether a is a function of b, b is a function of a, or neither. 1. a is the diameter of any U.S. coin and b is its value. 2. a is the universal product code for...

For each pair of variables determine whether a is a function of b, b is a function of a, or neither.

1. a is the diameter of any U.S. coin and b is its value. 2. a is the universal product code for any item at Walmart and bis its price. 3. a is the final exam score for any student in your class and b is his/her semester grade.