The amount of heat required to convert 10 grams of ice at $-{10}^{0}C$ to steam at ${100}^{0}C$ a

 $Q_1$ heat required for Ice to raise its temperature to $0^{0}C$  
 $Q_1=msdt=10\times 0.5\times 10=50cal$
 $Q_2$ is the heat to convert to water at $0^{0}C$   
 $Q_2=mL=10\times 80=800cal$
 $Q_3$ from $0^{0}C$ to ${100}^{0}C$ 
 $Q_3=msdt=100\times 1\times 100=1000cal$
$Q_4$ from water to steam $Q_4=mL=10\times 540=5400cal$  
$Q=Q_1+Q_2+Q_3+Q_4=7250cal$