so 12 mins to 600 feet
35 mins=1900 feet
find the slope which is change in top over change in bottom (aka slope) so to find do
(y1-y2)/(x1-x2)
we want, per minute, so put the time as x1 and x2
x1=12
y1=600
x2=35
y2=1900
subsitutte
(600-1900)/(12-35)=-1300/-23=56.5 per minute
the answe ris 56.5 feet per minute or the last answer