Alright noteddddd!btw, it is standard practice to quote AC voltages in RMS value.

Hence mains voltage @ 120VAC RMS going to a step down 10:1 transformer will produce 12VAC RMS.

Then you convert to 12 x 1.414 = 17V amplitude.

Since these are both multiplication you end up with the same result.

Just wanted to let you know.

how about my other questions? do you have any idea?

I know the Vpeak at the capacitor voltage, then use ripple factor= Vrms/Vaverage right?

the Vrms is it just Vpeak/square root (3) since it is a sawtooth waveform? ==> I get Vaverage, then what to do? How to relate it to the Vp-p (peak to peak ripple) so that I can use the equation sqrt(2)*f*C*Vp-p= I load = 101mA?