Canada shares a long land boundary with Alaska and a long boundary with the Arctic Ocean to the North.
It also has a very short boundary with the Pacific Ocean, around Vancouver.
It actually also shares a maritime (water) border with Greenland - although if we discount this kind of border, we can accept Greenland as the correct answer.
Humans impact the physical environment in many ways: overpopulation, pollution, burning fossil fuels, and deforestation. Changes like these have triggered climate change, soil erosion, poor air quality, and undrinkable water.
Since you did not give options, I will just help you out by saying that Implied Powers are powers that are <em>Not stated directly but are suggested to be true</em>