A car is driving down a road at a normal speed of 50 mph. It enters a hilly area of gradual incline and decline, where it must drive 50 miles uphill and then 50 miles downhill. If this 100-mile section of road takes 2.6 hours to
traverse instead of the expected 2 hours (the time it would take if the road was completely flat), determine the
speed that the hills add or subtract when going over.
A. 24 mph
B. 32 mph
C. 37 mph
D. 12.5 mph

16.9 times 2.85

step-by-step explanation:

depending on others is critical to survival. my source is apex!

step-by-step explanation:

answer: 204

step-by-step explanation:

we are told that the revenue is

x⋅(4080−10x)=−10x^2+4080x

this is a quadratic function, so to maximize it we should find the x-value of its vertex. recall that the x-value of the vertex of the parabola ax^2+bx+c is given by the formula −b/2a.

so in this case, we have a=−10 and b=4080, so the x-value of the vertex is

−b/2a= −(4080)/2(−10)=204