If each set of bivariate data has a causal relationship, determine the explanatory and response variables for each set of data.
a. Number of hours spent reading and page number on which you are reading
b. Calories burned and number of minutes of exercising
c. Amount paid as income tax and the amount of a paycheck
d. Pounds of hamburger used to make a meatloaf and number of people that can be fed from the meatloaf