Carnot cycles in thermodynamics

[ndavis]

Homework Statement

A heat engine operates in a Carnot cycle between 75.0°C and 353°C. It absorbs 21000 J of energy per cycle from the hot reservoir. The duration of each cycle is 2.00 s.

Homework Equations

W=Qc-Qh, W=-P change in temperature

The Attempt at a Solution

I attempted to solve by converting celsius to kelvins,then finding the percent

 

[vela]

You never actually said what the problem asked for. Is it just the efficiency?