Please help I don’t understand physics

This question is worth 54 points ! rock falls from a ledge to the ground what energy conversion occurs during this process a potential to kinetic b kinetic to potential c thermal to mechanical d chemical to mechanical

How many molecules are present in 3 mols of silicon dioxide (sio2)?

Which of the following is a characteristic shared by both electron and light microscopes? a. they both employ the use of objective lenses. b. both microscopes require an internal camera to visualize the specimen. c. both microscopes have a resolving power of 0.01 nm. d. they both utilize white light to magnify the specimen.