The popularity of operating systems is determined by studying the share of computer sales worldwide.

yep

Explanation:

answer; ///i believe that the correct answer is (copper);

to change your username, you must:

1) make sure what the username you want to change to is allowed in this community

2) contact a administrator (for example, jaysl)

3) through pm, tell the admin what you want to change to

4) if the username is allowed, it will be changed in a matter of seconds (minutes at most)

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