1. A boy starts jogging with a speed of 4.0 m/s and reaches a speed of 5.0 m/s after covering a distance
of 9 m. What is the boy's acceleration? 5
(15 Points)
0.50 m/s^2
1.0 m/s^2
2.0 m/s^2
3.0 m/s^2

diagram is missing, but i will try to explain your doubt.

answer:

amplitude is the maximum displacement or distance moved on a point of a vibrating body or wave measured from its equilibrium position.it is equal to half the length of vibration path.

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.

the part of the wave he is travelling on is the crest

i think the answer is a, hope this : )