Answer
a. About 0.22 kg/day.
b. It would take about 4.5 days.
Work Step by Step
a. To find the amount of fat burned in a day, multiply the power, the time (one day), and the mass/joule conversion for fat.
$$m=(95\frac{J}{s})(\frac{86400s}{day})\frac{1.0kg\;fat}{3.7\times10^7J}=0.22\frac{kg}{day}$$
b. Find the number of days needed to burn 1 kg this way.
$$(1.0kg)(\frac{1\;day}{0.2218kg})=4.5\;days$$
