This food chain is incomplete. two groups of organisms are missing. one group of organisms that is missing are the producers, plants and other photosynthetic organisms. they turn sunlight into chemical energy. what is the other missing group and what do they do? a) carnivores that eat only meat. b) herbivores that eat only plants. c) predators that prey on all other levels of consumers. d) decomposers that recycle matter back into the food chain.

Air pressure is measured in pascals. for a professional american football game, the ball should be inflated to about 90,000 pascals. scientists studied the effects of air temperature on the pressure inside american footballs by taking these steps: 1. prepare 100 footballs. 2. measure each football's air pressure. 3. divide footballs into 10 groups. 4. place the groups in different lockers cooled to different air temperatures. 5. after 12 hours, remove the footballs from lockers. 6. measure each football's pressure again. 7. compare the new pressures to the starting pressures. what two terms best describe the variable "air pressure inside the football" in this experiment? independent, qualitative independent, quantitative dependent, qualitative dependent, quantitative