PLEASE HELP!!!!!!

18. you make a purchase of $1,987.54 using a rewards card that gives you 2% cash back if the credit card has a 17.75% APR and you do not make a payment the first month how much is a difference between the first month's interest and the reward?
a 10.35
b 19.48
c 29.40
d 28.81

19. you have four credit cards each has a balance of $950 but their credit limits are $1,200, $2,200, $2,400, and $3,000 paying off and closing which card would decrease your debt ratio?

a 3000 limit
b 2200 limit
c 2400 limit
d 1200 limit