Pls answer if u know the answer ^w^ thx! Friction .

A) is always and unwanted force

B) works in the opposite direction of motion

C) causes machines to work 100 percent efficiently

D) can be increased using lubricants, like oil

Ajogger accelerates from rest to 4.86 m/s in 2.43 s. a car accelerates from 20.6 to 32.7 m/s also in 2.43 s. (a) find the magnitude of the acceleration of the jogger. (b) determine the magnitude of the acceleration of the car. (c) how much further does the car travel than the jogger during the 2.43 s?

Samir watches a 100-minute movie on his spaceship. maria's spaceshipe flies in the same direction as samir's spaceship but she observes his move to last 125 minutes and his spaceship to be 40 m long. how long does samir observe his own spaceship to be? according to an observer on earth, planet x is stationary. maria and samir depart earth on their spaceships at the same time, each flying at 0.5c. maria flies toward planet x and samir flies in the opposite direction. according to maria, her voyage to planet x takes 9 years. how many years does marias voyage take according to samir?

Alandscaper is shopping for landscaping materials. she wants to use materials through which water flows easily. which materials should she choose? check all that apply. clay gravel granite rocks with cracks loosely packed soil