The densities, in grams per cubic centimeter, of certain transition elements are as follows: 8.95, 7.14, 8.90, 4.50, 7.43, 8.91, and 7.14. Wha the mean density of these transition elements?

Aradio signal from a gps satellite take only about 0.067 seconds to reach a gps reciever. if the speed of light is about 300,000km/s, then approximately how far away is the reciever from from the satellite?

May someone me with these science questions

Which theory was contradicted by experiments with the photoelectric effect? light spreads out after it passes through a small opening. as soon as light strikes metal, electrons will be ejected. visible light, regardless of color, will cause the ejection of electrons when striking metal. the kinetic energy of ejected electrons depends on the frequency of light that strikes the metal.