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.

If the heat engine is a perfect carnot cycle engine, thenefficiency = (t2-t1)/t2   where t1=temperature of cold reservoir ( ° k) = 135            t2=temperature of hot reservoir ( ° k)   = 325thereforeefficiency = (t2-t1)/t2 = (325-135)/325 = 0.5846 = 58%  note: this is the theoretical maximum efficiency of a perfect heat engine.   real-life engines do not achieve this value.

The answer is -6hope this

Answerapply an acl that has all deny ace statement;

Answerthe distance between the two ends of the galaxy is 150,000 light years;