When referring to a megabyte for disk storage, the hard drive manufacturers use the standard that a megabyte is 1,000,000 bytes. This means that when you buy a 250 Gigabyte Hard drive you will get a total of 250,000,000,000 bytes of available storage.
A food chain only follows just one path as animals find food. eg: A hawk eats a snake, which has eaten a frog, which has eaten a grasshopper, which has eaten grass. A food web shows the many different paths plants and animals are connected. eg: A hawk might also eat a mouse, a squirrel, a frog or some other animal.
Every living organism needs energy to live. Plants get their energy from the Sun, some animals get their energy from eating plants, and other animals get energy from eating other animals. A food chain is a way of organizing living things by what they eat. It shows who's eating who. The arrows in a food chain show the flow of energy. Everything in the food chain is either a producer or a consumer.