Stars begin to form from clouds of gas in space. The cold temperatures and high densities (compared to elsewhere in space, but would be considered a vacuum on Earth) of these clouds allow gravity to overcome thermal pressure and start the gravitational collapse that will form a star.
<span>Causes Of Melanoma. Ultraviolet rays Most skin cancers are caused by too much exposure to the sun's ultraviolet (UV) rays. The two types of UV rays that cause melanoma are UV-A and UV-B rays.</span>
Geiger-Muller tube is instruments requires you test three times the background of the work area.
<u>Explanation</u>:
These detectors are gas filled detectors and hence requires time for responding to the value. This time is taken because during this period it collects the electric charges and features of the electric circuit. It also gets stabilized during this period. This device has thumb rule i.e one must wait or hold for at the least 3 times the time constant before getting the precise and accurate reading. The time constant order is 10 seconds for the ionization chamber but for the Geiger counter it can vary from seconds to greater than 20 seconds
Sediment; There is a source of heat that was not included in the question to create all the other choices.
Sister chromatids are two identical copies of Chromosome that is formed by the replication of a single chromosome.
This copies are formed during mitosis. Later on, these two sisters chromatids will grown into two different Cells
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