In which stage of a stars life does it undergo hydrogen fusion?

In an estuary, there is shallow, brackish water. what component of an estuary is this an example of? organism population species habitat

The physical processes that create most of earth's physical features, including mountains, are known as

Stone mountain was formed during the formation of the blue ridge mountains around 300-350 million years ago and is considered part of the appalachian mountains. it formed as a result of the upwelling of magma from within the earth's crust. this upwelling, or solidified to form the that became stone mountain.