Question

In order to stop a car in shortest distance on a horizontal road, one should
(a) apply the brakes very hard so that the wheels st rotating
(b) apply the brakes hard enough to just prevent slipprn
(c) pump the brakes (press and release)
(d) shut the engine off and not apply brakes.

Answer 1

(b) apply the brakes hard enough to just prevent slipprn

Explanation: 

In order to stop a car in shortest distance on a horizontal road, Maximum possible force of friction by applying brakes is needed. Maximum force of friction can only be achieved when the surfaces in contact are just on the verge of slipping but do not slip. In this situation the limiting/maximum static force of friction come into action. So apply the brakes hard enough to just prevent slipping.