The scientists predict that the presence of activated ras in the double mutant r7 precursor cell will enable the cell to differentiate into an r7 precursor cell

The answer is c) tons

The last option water because it is slow

Producers (autotrophs) are in the bottom (first) trophic level, primary consumers are in the second trophic level, secondary consumers are in the third trophic level and tertiary consumers are in the top trophic level. energy moves through the trophic levels when one living organism is being consumed by another. moreover, energy level becomes lower as it moves up the energy pyramid because of it being released as heat. food chain is when there is a single pathway of energy transfer whereas a food web is when there are multiple pathways of energy transfer.