A solid floats in a liquid at `20^@`C with 75 % of it immersed. When the liquid is heeated to `100^@`C, the same solid floats with `80%` of it immersed in the liquid. Calculate the coefficient of expansion of the liquid. Assume the volume of the solid to be constant.
A. `8.33 xx 10^(-4)//^(@)C`
B. `83.3 xx 10^(-4)//^(@)C`
C. `833 xx 10^(-4)//^(@)C`
D. `0.833 xx 10^(-4)//^(@)C`