1) The word "oxygen" contains two vowels: O and E.

2) The Amazon rainforest produces more than 20% of the world's oxygen.

3) Emma Stone is an American actress known for her roles in films such as "La La Land," "Easy A," and "The Help." She has received critical acclaim and several awards, including an Academy Award, for her performances, establishing herself as a talented and versatile actress.

4) The Federal Reserve System, often referred to as the Fed, is the central banking system of the United States.