Heidi is preparing for the national gymnastics competition. the table below shows the number of hours heidi spent preparing for a gymnastics competition over a period of five months:
month 1 2 3 4 5
hours 2 3.5 5 6.5 8
did heidi increase the number of hours of practice linearly or exponentially?
a. linearly, because the table shows an equal increase in hours for an equal increase in months
b. exponentially, because the table shows an equal increase in hours for an equal increase in months
c. linearly, because the table shows that hours increase by an equal factor for an equal increase in months
d. exponentially, because the table shows that hours increase by an equal factor for an equal increase