Coal tar (black material) is ............. before spreading on roads.

Coal tar is a mixture of almost........substances.

Two drawings, each of 3 balls, are made from a bag containing 5 white balls and 8 black balls, the balls not being replaced before the second trial. Find the probability that the first drawing will give three white, and the second three black balls.

Two drawings each of 3 balls, are made from a bag containing 5 white and 8 black balls, the balls being replaced before the second trial. Find the chance that the first drawing will give 3 white, and the second 3 black balls.

What is coal tar? What are its uses?

A box contains 12 balls out of which x are black. If one ball is drawn at random from the box, what is the probability that it will be a black ball ? If 6 more balls are put in the box, the probability of drawing a black ball is now double of what it was before. Find x .

A car travels due east on a level road for 3 km. It then turns due north at an intersection and travels 4 km before stopping. The magnitude of the resultant displacement of car is

When brakes are applied in a car,the brake-shoes apply frictional force on the wheels.these forces are internal for the system(car).For retardation,external forces ust act on the system.The force of friction at the road surface remains the same before and after teh brakes are applied (f = mu N) .How does the car stop?

In thermal power stations, coal is burnt to produce steam for generation of electricity. The smoke produced is passed through electrostatic precipitators before allowing it to escape into the atmosphere. Answer the following question : Which property of colloidal solution is used in an electrostatic precipitator?

In thermal power stations, coal is burnt to produce steam for generation of electricity. The smoke produced is passed through electrostatic precipitators before allowing it to escape into the atmosphere. Answer the following question : Why is smoke passed through electrostatic precipitators in thermal power stations?