Air flows through a pipe of diameter 10 cm made of drawn tubing. at a particular location, its static temperature is 50°c. how much longer should the pipe be so that at the exit (static conditions 1 atm and 20°c), the flow is at mach 0.9?

A)-explain briefly the importance of standards in engineering design. b)- what is patent? c)-explain the relationship between these standards: b.s. and b.s.en d)- in engineering design concepts, types of loads and how they act are important factors. explain.