Leni opened a savings account that pays 0.8% interest, compounded quarterly. Her initial deposit was $50. How long would she have to leave the money in the account for it to double?

I'm pretty sure it's b). i try drawing the functions out and b is the one that stands out or isnt a "line"

1. isolate the variable, in this case, d. subtract 35.5 on both sides of the equation.2. 52 subtracted by 35.5 is 16.53. therefore your answer would be d= 16.5this is the basics of pre algebra, isolating variable through adding, subtracting, multiplying, and dividing, if you have any other questions to ask just comment!