Scott and harry went cycling every day. they increased the number of minutes of cycling every week as described below: scott: cycled for 10 minutes every day in the first week, 15 minutes in the second week, 20 minutes in the third week, and 25 minutes in the fourth week. harry: cycled for 10 minutes every day in the first week, 20 minutes in the second week, 40 minutes in the third week, and 80 minutes in the fourth week. which statement best describes the methods used by scott and harry to increase the time they spent cycling?
a. scott's method is linear because the number of minutes increased by an equal number every week.
b. harry's method is linear because the number of minutes increased by an equal factor every week.
c. both harry's and scott's methods are exponential because the number of minutes increased by an equal factor every week.
d. both harry's and scott's methods are exponential because the number of minutes increased by an equal number every week.