As you did not state what the question is you just wrote a statement, I am guessing this is a True or False question. If there is more to the question please comment and Id be happy to help you answer more but if this is T/F then Ill answer it here right now.
A main-sequence star maintains a stable size as long as there is enough hydrogen to fuse into helium. True or False?
Answer: True
Hope this Helps, good luck, and comment if you need help on anything else :)
Answer:

Explanation:
In an atom, there is a dense center known as the nucleus. It is made up of two subatomic particles: <u>protons</u> and <u>neutrons</u>. The protons have a positive charge and the neutrons have no charge, so overall the nucleus is positively charged.
The third subatomic particles, negatively charged electrons, are located around the nucleus in a cloud.
The particles in the nucleus are
.
The geologist time scale was formed when scientists studied rock layers and index fossils worldwide. With this information, they placed Earth's rocks in order by relative age. Later, radioactive dating helped determine the exact age of the divisons in the geologic time scale.
This scale is organized by the 4.6 billion years of earth's history into sections based on important changes seen in the geologic record. The largest intervals are called eons, with each eon containing many millions of years.
In precambarian time the processes that affect Earth's surface have lessened the erosion on the surface. Earth was being hit by meteorites every second. Now there is water erosion and there wasn't back then. The surface changes have lessened over time.