Question: what is the difference between congress and senate? 

Answer: The Congress is made up of two parts, called houses.  The Senate is the upper house and each state has 2 senators.  The lower house of the Congress is the House of Representatives. It is larger than the Senate because the number of representatives from each state depends on the state's population and is not set at a specific number.  Each house of Congress has varying responsibility and rights.  So, in short, the Senate is just one half of the Congress.
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