Chem questions (State of matter calculations)

I'm getting lost on these 2 questions, so help would be greatly appreciated. Question #1 is worth 3 pts, question #2 is worth 5 pts.

1) The temperature of 12 L of gas is raised from 25 to 50 degrees C, what will the new volume be if mass and pressure are kept constant? Show your work.

2) Calculate the volume of 36.0g of carbon monoxide at STP.
- note - I've already calculated the molar mass to be 1008.36 mol, not sure if this is needed or not for the question.

Thanks!

1) (P1*V1)/T1=(P2*V2)/T2
Since pressure remains a constant, we can ignore it.
V1/T1=V2/T2
12/298=V2/323 (NB we have to change degrees C into degrees K)
V2=13.01 L

2) At STP, 1 mole of any gas = 22.8 L
1 mole of CO = 22.8 L
1 mole of CO = 38g
38g of CO = 22.8 L
36g of CO = (36/38)*22.8
36g of CO = 21.6 L

Note: if your teacher prefers you using 24 L as the volume of 1 mole of a gas, then the answer will be 22.7 L.

I hope the workings are clear and will help :)