Help pl! If the sin 30° = one over two, then which statement is true? (6 points)

Group of answer choices

cos 150° = 1, because the cosine and sine are supplements

cos 150° = 0, because the cosine and sine are supplements

cos 60° = 0, because the cosine and sine are complements

cos 60° = one over two, because the cosine and sine are complements

The interior angles formed by the side of a hexagon have measures of them up to 720° what is the measure of angle a

Mis the midpoint of rq if rm equals 2x + 5 and mq equals 4x - 9 what is the length of rq

Submarines control how much they float or sink in the ocean by changing the volume of air and water contained in large ballast tanks. when the tanks are completely full of water, the submarine increases its overall mass and sinks down to the bottom. when the tanks are completely full of air, the submarine reduces its overall mass and floats to the surface. depending on the density of the seawater surrounding the submarine, it will pump seawater in or out of the tanks in order to achieve the same overall density as the sea water and float neutrally in the water. the volume of the submarine never changes. when the tanks are completely full of water, a submarine with a volume of 7.8\times10^3\text{ m}^37.8×10 3 m 3 7, point, 8, times, 10, start superscript, 3, end superscript, space, m, start superscript, 3, end superscript has a total mass of 8\times10^6\text{ kg}8×10 6 kg8, times, 10, start superscript, 6, end superscript, space, k, g. the density of the seawater is 10^3\text{ kg/m}^310 3 kg/m 3 10, start superscript, 3, end superscript, space, k, g, slash, m, start superscript, 3, end superscript. to make that submarine float neutrally, and neither float nor sink in the ocean, what volume of water does that submarine need to subtract from its tanks?