An ice cube of dimension \( 60 \, \text{cm} \times 50 \, \text{cm} \times 20 \, \text{cm} \) in placed in an insulation box of will thickness \( 1 \, \text{cm} \). The box keeping the ice cube at \( 0^\circ \text{C} \) of temperature is brought to a room of temperature \( 40^\circ \text{C} \). The rate of melting of ice is approximately: (Latent heat of fusion of ice is \( 3.4 \times 10^{5} \, \text{J kg}^{-1} \) and thermal conducting of insulation wall is \( 0.05 \, \text{W m}^{-1}\,\!\!^\circ\text{C}^{-1} \) )
