Suppose you have a container filled with iron and sand. you can separate the iron from the sand if you so this is a
a) use a magnet; mixture.
b) melt the sand; mixture.
c) add baking soda; chemical compound.
d) dissolve the sand in water; solution.

Glass is transparent to visibile light under normal conditions; however, at extremely high intensities, glass will absorb most of the light incident upon it. this works through a process known as multiphoton absorption. in this process, several photons are absorbed at the same time. if very intense light whose photons carry 2ev of energy is shined onto a material with a band gap of 4ev, that light can be absorbed through two-photon absorption, because two photons have the right amount of energy to bridge the band gap. what is the minimum number of photons of 800-nm light that are needed to equal or exceed the band gap of fused silica glass

Acar is traveling 35 mph on a smooth surface . if a balanced force is applied to the car what happens?

Aplane's average speed between two cities is 600 km/h. if the trip takes 2.5 hours, how far does the plane fly?