What constant acceleration is required to increase the speed of a car from 20 mi/h to 51 mi/h in 3 seconds

Explanation:

acceleration is the time rate of change of velocity

a = (51 - 20) / 3 = 10⅓ mi/hr/s

which should probably be converted to standard units.

10⅓ mi/hr/s(5280 ft/mi) / 3600 s/hr) = 15.15555... ≈ 15.2 ft/s²

which is roughly half the acceleration of gravity.

object 2 because all the other ones are wrong

igneous rocks also form where plates converge. the subducting plate melts as it sinks into the crust of the earth, and the melt rises into the overriding plate forming volcanoes. metamorphic rocks are formed mainly in the lithosphere, wherever there is high pressure and high temperature. -woods