A group of Advanced Open Water Divers plans to make two dives. The first dive is on a reef in 22 metres/80 feet of water for 20 minutes. The group then remains on the surface for 1 hour. The second dive is on a wreck in 18 metres/60 feet of water, with a planned bottom time of 30 minutes. What will be the ending pressure group after the second dive?A. LB. KC. SD. R

Antireflective coatings on solar cells are often made by applying a thin film of silicon nitride (sinx), which has an index of refractive of 1.2, on the top of the silicon solar cell, which has a refractive index of about 3.5. however, the sun emits radiation of various wavelengths which the solar cell absorbs, and the antireflective coating can only absolutely minimize the reflection of one of these wavelengths. the coating thickness is chosen to reduce the reflection of green/yellow light (e = 2.2 ev), which is the most intense color in the solar spectrum (shown below). which of the following coatings would minimize reflection of green/yellow light? the answer is 820 nm how? what is the angular width of the central maximum of an electron traveling at 2 x 108 m/s going through a single slit of width 1 mm.