Use the fact that the orbit of a planet about the Sun is an​ ellipse, with the Sun at one focus. The aphelion of a planet is its greatest distance from the​ Sun, and the perihelion is its shortest distance. The mean distance of a planet from the Sun is the length of the semimajor axis of the elliptical orbit. See the illustration. The mean distance of planet A from the Sun is 86 million miles. If the aphelion of planet A is 88.5 million​ miles, what is the​ perihelion? Write an equation for the orbit of planet A around the Sun.

Asteam power plant operates on an ideal reheat rankine cycle between the pressure limits of 15 mpa and 10 kpa. the mass flow rate of steam through the cycle is 12 kg/s. steam enters both stages of the turbine at 500°c. if the moisture content of the steam at the exit of the low-pressure turbine is not to exceed 10 percent, determine (a) the pressure at which reheating takes place, (b) the total rate of heat input in the boiler, and (c) the thermal efficiency of the cycle. also, show the cycle on a t-s diagram with respect to the saturation lines. (2.15 mpa; 45.0 mw; 42.6%)

Hydrogen atoms are excited by a laser to the =4n=4 state and then allowed to emit. what is the maximum number of distinct emission spectral lines (lines of different wavelengths) that can be observed from this system? 8 6 2 7 4 5 1 3 calculate the wavelength of the 4⟶14⟶1 transition. =λ=

4. if you were an astronaut on the moon, what would you experience? what would you see from your perspective?