Which 1972 event marked the beginning of this trend?

Which of the following are true of the united states legislature? select all that apply. the house of representatives has two representatives from each state. senators are elected for a six-year term. the leader of the house of representatives is called the speaker of the house. once a bill passes the house, it goes directly to the president to sign into law or to veto. a person must be 30 years old in order to run for the house of representatives.