Answer:

Explanation:
Given:
temperature at the hotter end, 
temperature at the cooler end, 
length of rod through which the heat travels, 
cross-sectional area of rod, 
mass of ice melted at zero degree Celsius, 
time taken for the melting of ice, 
thermal conductivity k=?
By Fourier's Law of conduction we have:
......................................(1)
where:
=rate of heat transfer
dT= temperature difference across the length dx
Now, we need the total heat transfer according to the condition:
we know the latent heat of fusion of ice, 



Now the heat rate:



Now using eq,(1)

