$7.$ A $2\mathrm{.}15$ g cashew nut is burned. The heat released raises the temperature of a $100\mathrm{.}0$ g sample of

water from $18\mathrm{.}2\backslash$deg C to $31\mathrm{.}5\backslash$deg C$.$ The mass of the nut after the experiment is $1\mathrm{.}78$ g$.$ Determine

the calorie content of the nut in Calories$/$gram$.$ Assume that the water is only able to absorb

$25\%$ of the heat released by the burning nut.

$[$ Given $1\mathrm{.}00$ Calorie $=4\mathrm{.}18$ kJ $]$