Can someone plz help me with this I’m not understanding it I watch the video but I don’t know what to do plz help and I need help with the questions too

When a book falls from a shelf to the ground without anyone pushing on it, no work is done on the book. true or false

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

If a substance is in the gas phase, which of qualities of the gas will stay constant? a: volume b: mass c: shape d: position of particles