Which force is responsible for giving a backpack on someone's back its gravitational potential energy?

Wavelength,frequency,and energy are related.what happens to a wave as it’s wavelength gets shorter?

Because light travels in a straight line and casts a shadow, isaac newton hypothesized that light is

Two students, each riding bicycles, start from the same apartment building and ride to the same building on campus, but each takes a different route. the first student rides 1100 m due east and then turns due north and travels another 1430 m before arriving at the destination. the second student heads due north for 1930 m and then turns and heads directly toward the destination.at the turning point, how far is the second student from the destination?