He speaks in a pleasant manner
A session is a period of time each year when members of congress “meet to discuss laws” so option 3) is the correct one.
The United States congress has two sessions within a two-year term, one per year. During these sessions, the congress meets to debate on passing new laws and acts. Any member of the congress can introduce a bill to be discussed later in the sessions.
Answer:
For Anna the opportunity cost of going to her good friend's birthday is two or three hours of sleep
