Work and power for a square thermodynamic cycle

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Homework Statement


An engine goes through a "square" circuit process (is btw "circuit process" this the correct term in English?) according to the diagram below:
Closed rectangular p-V cycle plotted with p in units of 10^5 Pa from 2 to 8 against V in units of 10^-3 m^3 from 2 to 8, with the corners at V = 3 and 7 and p = 3 and 7, traversed by arrows.


a) How much work is performed by the engine during one revolution in the circuit process?
b) What effect does the engine deliver if it takes 0.2 s for the circuit process to go through one revolution?

Homework Equations


W = p*V
P = W*t

The Attempt at a Solution


For a) we have simply the area within the square, which is 1.6 kJ.

For b) if we have W = 1.6 kJ and t = 0.2 s, then we should get P = 1.600 J * 0.2 s = 320 W. Why is this not correct?
 
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  • p-V diagram of a closed rectangular cycle: pressure p in units of 10^5 Pa on the vertical axis against volume V in units of 10^-3 m^3 on the horizontal axis, with corners at (3, 3), (7, 3), (7, 7) and (3, 7), arrows showing the loop runs counterclockwise.
    pv.png
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You should divide, not multiply - power is the rate at which work is done by the engine.