The flow of energy through living systems can be modeled as food chains, food webs, or energy pyramids. The energy organisms need to live and grow first enters the ecosystem when which of the following occurs? 1.Plants take in light energy from the sun. 2. Decomposers break down dead organisms 3.Primary consumers eat plants for food 4. Secondary consumers eat primary consumers

Johnny rode his bike 4 blicks down the street to his friend's house once he got to his friend house and realized he could not cone out to play he turned aroubd and went back home.what is displacement for the total bike ride? how did you determine this? what could we use as a reference point to determine he was in motion during his bike ride? why can you use it as a reference point