1) The concept of federalism involves the division of powers between a central government and regional or local governments, allowing for shared governance and autonomy for different levels of administration.

2) Elvis Presley, often referred to as the "King of Rock and Roll," has sold over one billion records worldwide.

3) The role of lobbyists in politics involves representing the interests of specific groups or industries and advocating for favorable policies or influencing decision-making processes within government institutions.

4) The largest known dinosaur, Argentinosaurus, weighed around 70-100 tons and measured up to 100 feet in length.