Final answer:
The United States Senate is composed of 100 senators, with each state having two senators. Senators serve for six-year terms and are elected directly by the voters of their respective states.
Step-by-step explanation:
The United States Senate is composed of 100 senators. Each state has two senators. This is specified in the Constitution and has been the case since the adoption of the Seventeenth Amendment in 1913, which allowed for the direct election of senators by the voters of their respective states. Senators serve for six-year terms and are elected during midterm and presidential election years.