Which of the following is true about rocks? a. rocks are composed of only one mineral. b. most rocks are a mixture of minerals. c. coal is not considered a true rock. d. rocks do not contain any nonmineral matter.

Choose the molecule that is described by each phrase. energy used during long activities:

After getting the slide and microscope ready, stella is eager to see the microscopic pond water specimen! she crouches around her microscope and aligns her eye with the microscope’s eyepiece. but she's only able to see a bright white light. at this point, no specimens or cells are visible on stella's pond water slide. after taking a moment to collect her thoughts, stella realizes she can't see any lifeforms because .

The breakdown of food is accomplished by enzymes. a. physical b. chemical c. mechanical d. none of the above