$6.$ For an APR of $7\%,$ how long will it take for a sum to double $($i$.$e$.,$ FV $=2*$PV$)$ at an annual compounding system? What if quarterly compounding or monthly compounding is applied?

Annual Quarterly Monthly

m $=1$ Calculator Excel m $=???$ Calculator Excel m $=???$ Calculator Excel

N $=??????$ Year $10\mathrm{.}24$ N $=?????????$ Quarters $39\mathrm{.}95$ N $=?????????$ Months $119\mathrm{.}17$

I $=$ APR $7$ #N$/$A I $=$ APR $7\%$ #N$/$A I $=$ APR $???$ #N$/$A

PV $=0$ PV $=???$ PV $=???$

PMT $=0$ PMT $=???$ PMT $=???$

FV $=2$ FV $=???$ FV $=???$

END$/$BGN$=0$ END$/$BGN$=???$ END$/$BGN$=???$