Which occurs more, a partial or total lunar eclipse? Why?

What type of light does this light bulb produce most (i.e. at what wavelength does the spectrum have maximum intensity)?

Your town is considering building a biodiesel power plant describe at least two advantages and two disadvantages

Two identical stars with mass m orbit around their center of mass. each orbit is circular and has radius r, so that the two stars are always on opposite sides of the circle. (a) find the gravitational force of one star on the other. (b) find the orbital speed of each star and the period of the orbit. (c) how much energy would be required to separate the two stars to infinity?