How many members are in the senate ? how often are they elected? ?

100 members are in the senate. They have 6 year terms and only about 1/3 will get re-elected.

Explanation:

for part one 100 members in the senate. For part two Senators serve terms of six years each and since that there are 100 senators roughly one-third of the seats are up for election every two years.

Explanation:

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