1. Consumers are basically animals and producers are plants. Producers (ex. grass) make their own food and get energy from the Sun. Consumers (ex. rabbit) receive food and nutrients from producers and/or consumers.
2. Decomposers are important because they break down dead plants and animals. If they weren't there, plants, wouldn't get nutrients and waste would pile up.
3. Sorry-- I don't remember what chemosynthesis is.
4. I'd suggest looking up a food chain and going to images-- it's simple to find a diagram with all five of those. Sorry-- I can't think of any off the top of my head
5. The Sun.
Sorry-- I've only got some of it. I'm sure looking up #3 and #4 are easy to find answers to. Hope this helps. :)