Erin is а pаrt оf her high schооl's mаrching band. The band practices for hours for the upcoming Friday night football game's halftime show each week. The band is considered one of the best in the state, and each band member has to display a high level of talent and endurance to perform at such a high level. The band has other high school brands that it considers rivals. When two bands compete, back to back, at halftime, the crowd cheers indicate which band performed the best. This is an example of how marching band is ___________________________.