During childhood, siblings are a source of conflict and frustration as well as a support system. Adolescence may affect this relationship differently, depending on sibling gender. In same-sex sibling pairs, intimacy increases during early adolescence, then remains stable. Mixed-sex siblings pairs act differently; siblings drift apart during early adolescent years, but experience an increase in intimacy starting at middle adolescence. Sibling interactions are children's first relational experiences, the ones that shape their social and self-understanding for life. Sustaining positive sibling relations can assist adolescents in a number of ways. Siblings are able to act as peers, and may increase one another's sociability and feelings of self-worth. Older siblings can give guidance to younger siblings, although the impact of this can be either positive or negative depending on the activity of the older sibling.
At what stage to mixed-sex siblings generally experience an increase in intimacy?
middle adolescence

In the film Knute Rockne, All American, Knute Rockne (played by Pat O'Brien) delivers the famous "Win one for the Gipper" speech, at which point the background music swells with the "Notre Dame Victory March". George Gipp was played by Ronald Reagan, whose nickname "The Gipper" was derived from this role. This scene was parodied in the movie Airplane! with the same background music, only this time honoring George Zipp, one of Ted Striker's former comrades. The song also was prominent in the movie Rudy, with Sean Astin as Daniel "Rudy" Ruettiger, who harbored dreams of playing football at the University of Notre Dame despite significant obstacles.
Which person was a former comrade to Ted Striker in the film Airplane!?
George Zipp

The essential usefulness of a transistor comes from its ability to use a small signal applied between one pair of its terminals to control a much larger signal at another pair of terminals. This property is called gain. It can produce a stronger output signal, a voltage or current, which is proportional to a weaker input signal; that is, it can act as an amplifier. Alternatively, the transistor can be used to turn current on or off in a circuit as an electrically controlled switch, where the amount of current is determined by other circuit elements.
What is gain?
it can act as an amplifier