1. A communications satellite is at a geosynchronous orbit position (35,870 km above Earth's surface) and communicates with Earth at a frequency of 2.0 X 109 Hz. What is the frequency change due to gravity?
2. Stephen Hawking's derivation of the black hole temperature used the fact that the black hole's entropy is given by mplete the derivation using the thermodynamic de?nition of temperature 1/T 0S/ 0U . Assume that the black hole's energy is entirely mass-energy, that is, U Mc 2.