Answer
a. 14 million joules.
b. 3500 Calories.
Work Step by Step
a. The 65-kg person runs seven times per week, for 30 minutes each time, which gives a total of 210 minutes. Refer to Table 15–2 for the metabolic rate.
$$(1150\frac{J}{s})(\frac{210\;minutes}{week})(\frac{60s}{minute})\approx 1.4\times10^7\;J/week$$
b. Perform the calculation using Calories. The 65-kg person runs seven times per week, for half an hour each time, which gives a total of 3.5 hours.
$$(1000\frac{kcal}{h})(\frac{3.5\;hour}{week})\approx 3500 kcal/week$$
The person must consume 3500 Calories to make up for this energy loss.
