Why do hot spots form a “chain of volcanoes?

What is the energy of a photon of ultraviolet radiation with a frequency of 4.4 × 1015 hz? planck’s constant is 6.63 × 10–34

Light traveling in a medium with a refractive index 1.19 is incident on a plate of another medium with index of refraction 1.79. at what angle of incidence is the reflected light fully polarized?

Object a has a length of 3 cm, a width of 2 cm, and a height of 4 cm. object b is dropped into a graduated cylinder. it displaces 19 ml of water. the volume of object a is: a: greater than the volume of object b b: less than the volume of object b c: equal to the volume of object b