Why doesn't the skater ever regain his potential energy?

Need in all of themmm only answer if you know pls

Which law represents the thermodynamic statement of the conservation of energy of a system? a. the fourth law b. the first law c. the second law d. the third law

If angle "a" is 25°, angle "b" is: a) equal to angle c b) less than angle c c) greater than angle c