List and describe three ways that humans can change ecosystems and three ways that humans can protect ecosystems.

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

Science and technology are interdependent. advances in one lead to advances in the other. give an example of this phenomenon.

Which diagram correctly demonstrates the various forces acting on a ball moving horizontally with some speed?