Which statements describe the focus of an earthquake? Select three options.
It creates stress in rock.
It develops in the lithosphere.
It is the starting point of an earthquake.
It lies above the surface where rock breaks.
It begins about 100 kilometers below Earth's surface.

Amichelson interferometer operating at a 600 nm wavelength has a 3.02-cm-long glass cell in one arm. to begin, the air is pumped out of the cell and mirror m2 is adjusted to produce a bright spot at the center of the interference pattern. then a valve is opened and air is slowly admitted into the cell. the index of refraction of air at 1.00 atm pressure is 1.00028.how many bright-dark-bright fringe shifts are observed as the cell fills with air?