Please answer the following.

3x3-(9000)=x
x-3+=y
y+x=?

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

Aphysical change is a change in the size, shape,, or stafe of matter true or false

Matter is needed to transfer thermal energy bya. conductionb. convectionc. radiation d. both a & b.