What does the line of blue triangles mean on a weather map?

Cold front

Explanation:

A blue line with triangles on one side is a cold front. When you see a cold front on a weather map, it means a colder air mass is trying to replace warmer.

answer: what is the question?

explanation:

in mcculloch v. maryland (1819) the supreme court ruled that congress had implied powers under the necessary and proper clause of article i, section 8 of the constitution to create the second bank of the united states and that the state of maryland lacked the power to tax the bank.

gibbons v. ogden, (1824), was a landmark decision in which the supreme court of the united states held that the power to regulate interstate commerce, granted to congress by the commerce clause of the united states constitution, encompassed the power to regulate navigation.