Acopper water tank of mass 20kg contains 150 kg

How is coal extracted from mountaintop removal mines? a. dynamite is used to create underground tunnels where miners go to extract the coal. b. dynamite is used to break apart rocks and then draglines are used to remove the broken rock and reach the coal. c. coal in mountaintops is extracted by digging strips in the landscape to reach the coal. d. placer deposits in mountain river bottoms are removed by

The softest and hardest minerals are: softest hardest

Atorque acting on an object tends to produce a. equilibrium b. rotation c. linear motion d. velocity e. a center of gravity