Stella is interested in determining whether people have gotten more or less exercise since going under social distancing protocols. Zhe asks people, "Please estimate the number of hours of exercise you got each week before social distancing took effect" and then asks, "Please estimate the number of hours of exercise you got each week after social distancing took effect." Both of these variables are positively skewed. What are the scales of zer variables? Question 6 options: a) Zer independent variable is ordinal; zer dependent variable is interval. b) Zer independent variable is ratio; zer dependent variable is ratio. c) Zer independent variable is nominal; zer dependent variable is ratio. d) Zer independent variable is nominal; zer dependent variable is ordinal