Ice at `0^@C` is added to 200 g of water initially at `70^@C` in a vacuum flask. When 50 g of ice has been added and has all melted the temperature of the flask and contents is `40^@C`. When a further 80 g of ice has been added and has all melted the temperature of the whole becomes `10^@C`. Find the latent heat of fusion of ice.

Options

A. `3.8xx10^5 J//kg`
B. `1.2xx10^5 J//kg`
C. `2.4xx10^5 J //kg`
D. `3.0xx10^5 J//kg`

Answer

A