How does a dam negatively affect animals that live downstream? Check all that apply. It decreases the water level.
It changes the sediment and silt.
It decreases the chance for flooding.
It creates a natural barrier that hides prey.
It stops some animals from being able to travel upstream.

It decreases the water level

It changes the sediment and silt

It stops some animals from being able to travel upstream

Explanation:

answer; (a) he was a u.s senator for 38 years;

nothing certain is known about what happened, but it seems that the country declined gradually, perhaps due to bad government, or, more likely, due to a series of bad harvests, which resulted in widespread and recurrent famine.