Can you please tell me if these are right?

A gas has a volume of 2.8 L at a temperature of 27 degrees C. What temperature degrees C is needed to expand the volume to 15 L? (P and n are constant.)
I got 1334 degress C

Combined gas law problem a balloon is filled with 500.0 mL if helium at a temperature of 27 degress C and 755 mm Hg. As the baloon rises in the atmoshper the pressure and temperature drop what volume will it have when it reaches an altiude where the temperature is -33 degrees C and the prssure is 0.65 atm.
I got 609 mL.

Thanks.

1 answer

I agree with #1. #2 I get 611 mL.