Please, correct my essay.

The lecturer states that forensics is the science to solve crimes. Forensic biologists analyze blood, hair, and saliva to identify criminals. Forensic chemists look at powders and other materials for traces of drugs or explosives. Forensic anthropologists study bones to estimate how old people were when they died. A body farm is a outdoor lab. Inside, more than 40 bodies lie in various stages of decay. Scientists watch the bodies closely to see what happens to them over time due to weather, animals, bugs, and other things. These observations give them useful information about how to interpret what police find.