Is this right? Please help me

Which formula can be used to calculate the molar mass of ammonia (nh3)? molar mass of n + molar mass of h 3 × molar mass of n + molar mass of h molar mass of n + 3 × molar mass of h 3 × molar mass of n + 3 × molar mass of h

What can be found in the ionosphere

40dm3 of gas at 760 torr are heated from 5°c to 50°c what is the new volume