search for 36 43 43.16N 118 32 6.88W.
Sphinx Crest that you have on your figure. Put a placemark here. Zoom out to about
20,000 ft eye altitude so you can also find Sphinx Lake. You want to hike the straight-line distance between these two spots -
from Sphinx Crest to the western shore of Sphinx Lake (the northeast lake).
Calculate the gradient between them in feet per mile. The gradient is:
a) -0.009 feet/mile
b) 190 feet/mile
c) -1,719 feet/mile
d) -1,065 feet/mile