Answer:
2 h
Explanation:
Velocity =Distance/time ⇒ time = distance/speed
= 1440/720
= 2 h
Answer:
coal as a fuel source led to the invention of the printing press i think
Answer: temperature of the hot reservoir is 303.52K
Explanation:
Th=temperagture of hot reservoir
Tc=temperature of cold reservoir 263K
Eff=efficiency of the refrigerator
Cop=coefficient of performance
7
Eff=1/cop
Eff=1/7
Eff=0.142
Eff=1-263/th
0.142-1=-263/th
-0.858=-263/th
Th=303.52K