You gotta put more information out buddy
<span>If the interest is comounded every 2 months then you will
apply the interest 6 times in a year. So the value of n that you will plug into
your equation is 6 because there 12 months a year then it wll be compounded
every 2 months</span>
If the total bill is $85, and you want to leave a 15% tip, then you can calculate it as follows:
85 * 15%
= 85 * 15/100
= 85 * 0.15
= 12.75
The amount that should be left as a tip is D. $12.75.