For example, a 5 panel drug test checks for 5 drugs, while a 10 panel drug screen checks for 10 drugs. A standard 5 panel drug urine test is the drug test most frequently used by government agencies and private employers.
While a member of the senate is called a senator, a representative is simply called a congressman or a congresswoman. However, collectively, both senators and representatives are also referred to as congressmen. The word Senate comes from the Latin word senate meaning old man.
John C. Calhoun was an American congressman, secretary of war, seventh vice president, senator and secretary of state. He championed states' rights and slavery.