When climbing a mountain what would you predict about temperatures?

When you're climbing a mountain, the temperature decreases (it gets colder), at least in the first layer of the atmosphere, which is called troposphere. (There are four layers in the atmosphere but there are no mountains tall enough to reach the other 3 layers) and the 3 other layer's temperature changes significantly. So in short, the temperature decreases continuously the higher you reach the mountain.

Sequoia national park  /  inyo national forest, california, u.s. mount whitney is the tallest mountain in california, as well as the highest summit in the contiguous united states and thesierra nevada—with an elevation of 14,505 feet (4,421 m).