What percentage of the world’s supply of coltan is in Congo?

Agardener uses a wheelbarrow to move soil from a truck to his garden. on the first trip from the truck to the garden, the wheelbarrow is half-full of soil and the gardener applies a certain force to cause it to accelerate. on the second trip, the wheelbarrow is full of soil. although the gardener applies the same amount of force to the wheelbarrow, he cannot move it with the same rate of acceleration. what should the gardener do to move the wheelbarrow at the same rate of acceleration for the second trip?

Crowbar of 5 metre is used to lift an object of 800 metre if the effort arm is 200cm calculate the force applied

Aman throws a football straight into the air. as it rises, it slows down. which type of energy is the football gaining?