The coordinates of a spacecraft in the rotating Earth-Moon system coordinate frame are [-5500 5500]T. The velocity of the spacecraft is 11.83 km/s. Determine the Jacobi constant for the spacecraft and determine whether it can escape the Earth-Moon system. [-1.67. No because C < CL2]

If there was no gravity then their would be no downword force on the football to have it return the the grownd, and if there was no friction (mainly air friction) then there would be no opposing force the stop the ball from moving through the air allowing the ball to travle ∞.

Ican’t exactly answer this, but i can try to give a bit more info here.
astronomers are able to calculate a star’s life expectancy depending on its mass. (a larger star burns more gas, therefore having a shorter life span).
so astronomers can definitely predict the death of stars and the times they will die.
i hope this was in some way : )

Ithink it would be a concave lens.

107.1 mhz has higher energy photons. the photon energy increases directly proportional to frequency. however if the station operating on 90.5 mhz transmitter's power is 1.184 times or higher than that of the station operating on 107.1 mhz transmitter's power, then the 90.5 mhz signal will have higher energy because the additional photons makeup the difference. the total energy in electromagnetic radiation is the product of the energy per photon and the number of photons (i.e. amplitude of the wave) in the radiation.