A 65 kg speed skater is racing around a circular track. The track has a radius of 20 m. It takes the skater 10 seconds to complete one lap. The skater moves at a pace of 12.56 m/s. Calculate the skater's acceleration.

second mirror gathers light from a faraway object and reflects it to another mirror. - a.

photocells convert light energy to electricity

answer: the exterior temperature of commercial jet planes as they leave the stratosphere and return to the ground increases steadily.

explanation:

the lower most layer of atmosphere is troposphere which extends from 0 to 12 km above the surface of the earth. the temperature initially decreases as distance is increased from the earth's surface. commercial jets fly in lower part of the stratosphere. the stratosphere extends upto 50 km. the temperature in stratosphere starts rising again due to presence of ozone which traps the uv rays.

thus, when the planes leave the stratosphere and return to the ground, the exterior temperature increases steadily.

think its the third option