Answer:

Explanation:
It is given that,
Depth of Death valley is 85 m below sea level, 
The summit of nearby Mt. Whitney has an elevation of 4420 m, 
Mass of the hiker, m = 65 kg
We need to find the change in potential energy. It is given by :



or

So, the change in potential energy of the hiker is
. Hence, this is the required solution.
The appropriate response is Zero degrees. The beam will leave the two mirrors along a way parallel to the one it came in on. This is the guideline of the corner reflector, which is frequently utilized as a radar target. Take note of that the corner reflector utilizes three reflecting surfaces (that are set up at 90o from each other) rather than the two like are being utilized here. Wikipedia has a truly awesome drawing that shows this two-dimentional issue pleasantly. A moment connection is given to the article on the corner reflector and the 3-D angles.
Displacement = (straight-line distance between the start point and end point) .
Since the road east is perpendicular to the road north,
the car drove two legs of a right triangle, and the magnitude
of its final displacement is the hypotenuse of the triangle.
Length of the hypotenuse = √ (215² + 45²)
= √ (46,225 + 2,025)
= √ 48,250
= 219.7 miles .