CFAI MOCK am test strong family problem, monthly, interest, mortgage, remember

luckygiftvn

yo, i am looknig at band of interest problem 28. since when do we use annuities for mortgage rates? i know that BOI is like a WACC but i never remember seeing monthly compounding for a loan. am i wrong? am i losing it?
Those scientists better check their hypotenuses, dude!