# How do you calculate the amount of heat (in kJ) required to heat 4.14 kg of water from 21.50 C to 33.85 C.?

You need the specific heat of water which is 4.2 $\frac{k J}{k g . K}$.
Then you can use the relationship $E = m . c . \theta$ where $E$ is the heat energy involved, $m$ is the mass of the substance being heated, and $\theta$ is the temperature change.