During a test, the scientist may try to prove or disprove just the null hypothesis or test both the null and the alternative hypothesis. If a hypothesis specifies a certain direction, it is called one-tailed hypothesis.
A mountain pass (also called a gap, saddle, or col) is a passage over a mountain range. They typically occur in valleys between mountain ridges, in low points along mountain watersheds or just the lowest point on a mountain ridge between two peaks. They can be relatively short in length (the width of a ridge) or they can be valleys many miles long. Mountain passes are often the location where roads and railways are built to get through the mountains. Many of them have become famous throughout history for their importance in trade and commerce.
Switch to new thesaurus. chain of mountains, mountain chain, range of mountains, range, chain. geological formation, formation - (geology) the geological features of the earth. massif - a block of the earth's crust bounded by faults and shifted to form peaks of a mountain range. mountain pass, notch, pass - the location in a range of mountains of a geological formation that is lower than the surrounding peaks; we got through the pass before it started to snow.