The following table lists the speed of sound in various materials. Use this table to answer the question. The siren from a small town fire station is heard at a location 3 kilometers away. If the air temperature is 20°C, at what
velocity did the sound travel?
a.319 m/s
b. 331 m/s
c. 343 m/s
d. 387 m/s

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

In an experiment, how can i change human errors? be specific.

Why does gravity have a lesser than grater effect on higher altitudes?