In the air, there's nothing holding the body of the helicopter still - so the rotor blades spin one direction, but the torque applied to spin the rotors tries to spin the body of the helicopter in the opposite direction. The little rotor on the tail helps keep the body of the helicopter pointed in the same direction.
Balance on a bicycle is a matter of constantly correcting against falls, and it's easier when the speed is higher because the inertia of moving forward overcomes the need for corrective actions.
One major difference between Americans and Japanese is their cultural norms and values. For example, Americans tend to value individualism and independence, while Japanese tend to prioritize group harmony and collectivism. This can be seen in various aspects of daily life, such as communication style, decision-making processes, and social interactions. Additionally, the two cultures have different customs and traditions, including food, clothing, and holidays.
Quality of life refers to the overall well-being, satisfaction, and happiness that an individual or a community experiences in various aspects of their lives.