Analyze the food web in order to trace the flow of energy in the ecosytem shown?

You can analyze how much energy is consumed by an animal in the food web by the power of ten. It's really simple, actually. A fly has to get 100 grams of energy. It uses ninety for itself, and the other ten goes to the animal that consumes it. Say a spider eats that fly. The spider also needs 100 grams. So, if it gets ten grams from that one fly, it needs to eat nine other flies to reach its energy need for that day. And whatever eats the spider needs to eat nine other Spiders to reach its energy need. It continues like this for the whole web.