Hi could someone please help me with this problem of converting an AC input to DC for a cell phone charger:

And attached is my work and calculations for the problem part (a).

I feel somewhat hesitant about my solution, so could someone please go over it and give me some feedback? I based the assumption that this rectifier is safe for the phone on the avg. current and voltage in part (b). So basically, I solved part (b) to solve part (a). Is this correct?

 

There's no inconsistency in your method. It looks fine thus far.