When is it called when the Moon, Earth , and Sun line up and the tides on Earth are at there highest during high tide and lowest at low tide ? 1. Spring tides
2. Low tide
3. high tide
4. Neap tides

Three reasons of the deaths of native americans: new illnesses that their immune systems couldn't cope with. genocides so the settlers could have the good land.starvation from lack of rations and poor infertile land on resevations

Long term continuous groundwater monitoring, especially with warning systems and anthropic activity monitors