Answer: The correct answer is option B.
Explanation:
Mass of the sled = 10 kg
Initial speed of the sled = 2 m/s
Kinetic energy of the sled = 

Work done by the sled = 20 joules
The work done by the friction will be in opposite direction and equal to the magnitude of the work done of the sled that - 20 J.
Hence, correct answer is option B.
The speed of the ball moving is

what is momentum?
The momentum p of a classical object of mass m and velocity v is given by pclassical =mv.
For photons with wavelength λ,this equation does not hold.Instead, the momentum of the Photon is given by p Photon = h/λ
where,h is the planck's constant.
The momentum of the red Photon is
given:




since,the Photon and the ping-pong ball have the same momentum,we have



Therefore, if the red photon and the ping-pong ball have the same momentum, the ping-pong ball must have a speed of approximately

learn more about momentum of photon from here: brainly.com/question/28197406
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Answer:
If conditions are just right, you can see Polaris from just south of the equator. Although Polaris is also known as the North Star, it doesn't lie precisely above Earth's North Pole. If it did, Polaris would have a declination of exactly 90 degree.
Explanation: