What is this answer most energy enter the ecosystem through the process of

We just started a new lesson in chemistry and everyone hates it and i dont get it one bit. i hate school. h el p. balanced equationc3h8+5o2-> 3co2+4h2o1.) if you start with 14.8g of propane(c3h8) and 3.44g of oxygen, which is the limiting reactant -check my answer 2.)what mass of excess reagent is left over? 3.)what mass of carbon dioxide can be made? 4.)what mass of water is produced?

Significant figures are digits read directly from the measuring instrument plus one more digit, which is __ by the observer.

Define dew point. i am writing this part to be able to ask the question