Answer:

Explanation:
From the question we are told that:
Water flow Rate 
Initial Temperature 
Final Temperature 
Let
Specific heat of water 
And


Generally the equation for Heat transfer rate of water
is mathematically given by
Heat transfer rate to water= mass flow rate* specific heat* change in temperature



Therefore


Answer:
The heat input from the combustion phase is 2000 watts.
Explanation:
The energy efficiency of the heat engine (
), no unit, is defined by this formula:
(1)
Where:
- Heat input, in watts.
- Power output, in watts.
If we know that
and
, then the heat input from the combustion phase is:




The heat input from the combustion phase is 2000 watts.