Answer:
do it if it's Sunday why are you like this
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Answer:
The ACH is 12/h
Solution:
As per the question:
Area of the space, 
Height of the given space, h = 10 ft
Air flow rate, 
Now, to find the Air Change Rate (ACH):
We calculate the Volume of the given space:

Now, the ACH per min:
= 
Now, ACH per hour:
= 
Answer:
work will be positive when it is under polytropic expansion process
Explanation:
It states a polytropic process with n equal to 1.67. there is a polytropic expansion that mean work is positive and if it was polytropic compression then it would be negative
Also work during the process of polytropic is given as
the work will be positive when it is under the polytropic expansion process