Answer:
(d) a and c are correct
Explanation:
METALS : Metal are those materials which has very high ductility, high modulus of elasticity, good thermal and electrical conductivity
for example : iron, gold ,silver, copper
ALLOYS: Alloys are those materials which are made up of combining of two or more than two metals these also have good thermal and electrical conductivity and me liable property
for example ; bronze and brass
so from above discussion it is clear that option (d) will be the correct option
Answer:The Urban heat island temperature will be REDUCED.
Two Impacts of Rooftop gardens
1) provision of shade against Sunlight.
2) It helps to purify the air around the building.
Explanation: Rooftop gardens are gardens made on top of the roofs of buildings, it is a Green initiative aimed at helping to improve the overall Environment.
Rooftop gardens have several significant benefits which includes
Reduction of the surrounding temperatures and the Urban heat Island temperatures.
Rooftop gardens helps to shade the roof from the direct impacts of harsh weather conditions.
Generally, plants are known as air purifiers as they remove the excess Carbondioxide around the environment through photosynthesis, and they also help to release water vapor which will help to improve the humidity of the environment.
Answer:
the welding gun liner regulates the shielding gas.
Explanation:
The purpose of the welding gun liner is to properly position the welding wire from the wire feeder till it gets to the nozzle or contact tip of the gun. <em>Regulation of the shielding gas depends on factors such as the speed, current, and type of gas being used. </em>In gas metal arc welding, an electric arc is used to generate heat which melts both the electrode and the workpiece or base metal.
The electric arc produced is shielded from contamination by the shielding gas. The heat generated by the short electric arc is low.