In order to fly, you must have a device/mechanism that will release hot air, causing it to fly. A jet pack will do the job.
Answer:
=0.60
Explanation:
Given :Take
=1.4 for air

=r ⇒ r=16
As we know that

So 
=909.42K
Now find the cut off ration 



So efficiency of diesel engine

Now by putting the all values

So
=0.60
So the efficiency of diesel engine=0.60
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