On what does the heat required to increase the temperature of a substance depend?

Two substances $A$ and $B$ of the same mass are heated at a constant rate. The variation of temperature $\theta$ of the substances with time $t$ is shown in the figure. Choose the correct statement.

The $S.I.$ unit of specific heat capacity is

Water is used to cool radiators of engines,because

The specific heat of a substance varies with temperature as $c = 0.20 + 0.14t + 0.023t^2 \, (cal/g \cdot ^\circ C)$. The amount of heat required to raise the temperature of $2 \, g$ of the substance from $5 \, ^\circ C$ to $15 \, ^\circ C$ is: (in $, cal$)

The ratio of the heat capacities of two bodies is $1:4$. If the rate of heat loss is the same for both bodies under similar environmental conditions,then the ratio of the rate of fall of their temperatures is: