A. The pressure is lower as you gain altitude because there are more molecules of oxygen and nitrogen. B. The pressure is lower as you gain altitude because there are less molecules of oxygen and nitrogen. C. The pressure is the same because there is no change in the number of molecules.
The price of a cockatiel depends on a few factors. Firstly the price depends on whether or not the bird is tamed. For a tamed cockatiel it would cost around $80 - $120 and a untamed cockatiel would cost $15-$30 (AUS) Also the colouring of the cockatiel plays a part in the cost of the bird, as more rare colours (such as lutino or pearl cinnamon) may increase the cost of the cockatiel.
Cockatiels are members of the parrot family and very popular pets in households around the world. Measuring about 12 inches, they have been bred to display different colors not normally found in the wild. The cockatiel is native to Australia, where the bird is commonly referred to as a quarrion. Healthy cockatiels are known to live upwards of 25 years with proper care. With a lot of patience, cockatiels can be taught to talk, and even whistle your favorite songs. There are several types of cockatiels.