Please Answer both 1&2 accurately and I will thumbs up!

1. What is the mass velocity of air that can be handled in a 1/2 in schedule 40 horizontal steel pipe 320 ft long, if the air flows isothermally at 120F through the pipe? The pressure drops from 60 to 10 psig through the pipe?

2. Carbon dioxide at 80C enters a 2-in schedule 80 steel pipe at a gauge pressure of 500 kPa, and a velocity of 25 m/s. Assume adiabatic flow. (a) What is the maximum length of the pipe?

(b) What are the pressure and stagnation temperature of the gas at the end of the pipe at maximum length?