Which material undergoes radioactive decay?

Skulls of (1) modern gorilla, (2) australopithecus afarensis, (3) homo erectus, (4) homo neanderthalensis, (5) homo sapiens based on the diagram, which of the following best describes ways in which the physical appearance of h. neandertalensis and h. sapiens differ? (2 points)

Four types of motile cells in human body?

How does buring fossil fuels impact does carbon cycle? what large impact does this have on the envirnment?