Which best describes the purpose of a controlled experiment? A) to make sure the results of the experiment support the hypothesis
B) to prevent a dangerous condition resulting from a reaction
C) to examine whether one variable causes a change in another
B) to prevent an undesired change in a variable

20. threshold braking in the vehicle's braking system occurs when a. the brake pedal is pushed, heel on floorboard, with full foot pressure. b. the brakes are exerting full braking power, without traction loss. c. the driver begins pushing down the brake pedal, with moderate slowdown. d. the brakes just begin to take hold with a gradual slowdown.

Anybody wanna ? (picture included? )

You've already seen the value of 9.8 in this lesson. what's this value called? what quantity does it represent?