Yes, both of your answers are correct.
Since Death Valley is below sea level, the hiker increases altitude before stopping at 0 feet.
Percent of increase is given by the formula (amount of change)/(original amount) * 100. Your work is accurate.
Answer:
Step-by-step explanation:

<span>C = 2*pi*r
C = 2*pi*7
Exact Circumference: C = 14pi inches
C = 14*3.14
Approximate Circumference: C = 43.96 inches </span>