The altitude at which trees no longer grow varies depending on factors such as climate, soil conditions, and tree species. Generally, as altitude increases, the temperature decreases and the air becomes thinner, making it more difficult for trees to survive. However, some tree species have been known to grow at very high altitudes, up to around 14,000 feet (4,200 meters) in the Himalayas, for example. In general, above the tree line, which is typically around 11,000 to 12,000 feet (3,400 to 3,700 meters) in the temperate regions, trees no longer grow due to the harsh environmental conditions. **

The moon's altitude refers to its angular distance above the horizon. The moon's altitude changes throughout the night as it moves across the sky. At its highest point, the moon's altitude can reach around 90 degrees, which means it is directly overhead. The moon's altitude is an important factor for astronomers and navigators when determining its position in the sky. **

The legality of a flight altitude depends on various factors such as air traffic control regulations, airspace restrictions, and the specific flight plan. Pilots must adhere to the altitude restrictions set by air traffic control and comply with any airspace regulations in the area they are flying. Additionally, the aircraft's performance capabilities and the weather conditions also play a role in determining the legal flight altitude. Therefore, without specific details about the flight and the regulations in place, it is not possible to determine the legality of the flight altitude. **

Altitude difference refers to the vertical distance between two points, typically measured from sea level. It is the difference in elevation between the highest and lowest points in a given area. Altitude difference is an important factor in determining the topography and terrain of a region, and it can have significant effects on weather patterns, ecosystems, and human activities such as agriculture and transportation. **

At an altitude of 1000 meters in the mountains, you can find a variety of flowers such as alpine aster, mountain avens, alpine forget-me-nots, and alpine gentians. These flowers have adapted to the cooler temperatures and harsh conditions of higher altitudes. Their vibrant colors and unique shapes make them a beautiful sight to behold in the mountainous regions. **

Clouds float at various altitudes depending on their type. For example, cirrus clouds can be found at high altitudes of 20,000 feet or more, while cumulus clouds typically form at lower altitudes around 6,500 feet. Altostratus clouds are found at mid-level altitudes around 6,500 to 20,000 feet. Overall, clouds can be found floating at different altitudes in the Earth's atmosphere, ranging from low to high levels. **

The altitude at which a person can survive varies depending on factors such as acclimatization, physical condition, and individual tolerance. Generally, the human body can adapt to higher altitudes over time, but the threshold for survival without supplemental oxygen is typically around 18,000 feet (5,500 meters). Above this altitude, the air becomes too thin to provide sufficient oxygen for the body to function properly, leading to altitude sickness and potentially life-threatening conditions. However, with proper acclimatization and gradual ascent, some individuals can survive at even higher altitudes. **

The altitude at which one can survive varies depending on factors such as individual health, acclimatization, and the rate of ascent. Generally, humans can survive at altitudes up to around 18,000 feet (5,500 meters) without experiencing severe altitude sickness. However, prolonged exposure to altitudes above 26,000 feet (8,000 meters) without supplemental oxygen is not sustainable for most people due to the lack of oxygen at high altitudes. It is important to acclimatize properly and be aware of the symptoms of altitude sickness when ascending to high altitudes. **