ᴴᵉˡˡᵒ ʷʰᵃᵗ ᵃʳᵉ ʸᵒᵘ ᵈᵒⁱⁿᵍ ᴵᵐ ᵃ ᵇⁱᵗ ˢᵃᵈ ᴸᵉᵗˢ ᵗᵃˡᵏ
ᶠⁱⁿᵈ ᵐᵉ ʰᵉʳᵉ
ᵇʳᵃⁱⁿˡʸ.ᵗᵒᵈᵃʸ

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.

How is sound energy produced a. vibrating objects b. objects being heated c. temperature differences d. stationary objects

What component of earth’s atmosphere exists entirely as a result of photosynthesis?