Once a law is a "law" it can be repealed by Congress or overturned by the Supreme Court, if it's unconstitutional.
If it hasn't yet become a law, it's just called a "bill." Laws are bills that passed votes in both houses of Congress and were then signed into law by the President.
There lots of things that can prevent a bill from becoming law. If either the House of Representatives or US Senate (or both) can't muster enough votes, the bill won't become law. The bill could be sent to a House or Senate committee and die there; or it could be killed on the Senate floor if a Senator filibusters and the bill sponsors can't get enough votes to break the filibuster. The President could veto it outright, or he could stop the bill with a "pocket veto," which means Congress sends the bill to the President less than ten days before a recess, and he neither signs it nor returns it to Congress before they go out on break.
Yes, the president can sign a bill that become a law.
it is the law of gravitation
A theory, when proven over time, can become a law. Example: Law of Gravity and Theory of Evolution
Depends which country you are in.
A bill does become a law when a president signs it, but a bill can also become a law without the presidents signature.
a law or regulation
I studied criminal law to become a law enforcement officer.
If you break the law, you will be a criminal in the particular law-enforcement and will be penalized.
If a bill is vetoed it can become a law by being sent back to the House of Representatives and the Senate. If 2/3 of both the House of representatives and the Senate vote yes for the bill to become a law, it becomes a law without a signature.
A law that is not done right is a law that is untrue. This is usually when a law that was not passed.
It became law on May 4, 2010.
Go to law school, get your law license, and study environmental law.