Answer:
63.36 W/m
Explanation:
The heat loss of an organism is given by :
...(1)
Where
y is heat loss in watts and x is the length of the organism in metres.
We need to find the rate of change of heat loss when the organism is 0.8 m in length.
Differentiate equation (1) wrt x.

Put x = 0.8 m in above equation.

So, the rate of change of heat loss when the organism is 0.8 m in length is 63.36 W/m