Answer:
a) 
b) 
Explanation:
From the question we are told that:
Pressure 
Diameter 
Generally at sea level

Generally the Power series equation for Mach number is mathematically given by



Therefore
Mass flow rate



Generally the equation for Velocity at throat is mathematically given by
)
Where


Therefore

Generally the equation for Mass flow rate is mathematically given by



A8 is the answer because yea and because I am a teacher
Answer:
3) the pressure drop across high MERV filters is significant.
Explanation:
MERV (Minimum-Efficiency Reporting Value) is used to measure the efficiency of filter to remove particles. A filter of high MERV can filter smaller particles but this causes an increase in reduced air flow that is an increase in pressure drop. High MERV filters capture more particles causing them to get congested faster and thereby increasing pressure drop.
Excessive pressure drop can cause overheating and lead to damage of the filter. The pressure drop can be reduced by increasing the surface area of the filter.
Answer:
Welding is a fabrication process whereby two or more parts are fused together by means of heat, pressure or both forming a join as the parts cool. Welding is usually used on metals and thermoplastics but can also be used on wood.
Explanation: