5. It has been generally concluded that Mars at one time had significant amounts of water. What evidence is there to support this conclusion?

Explained

Explanation:

The general conclusion that Mars at one time had significant amounts of water can be supported by following evidences

1. The flatter northern plains of Mars may once have hosted an ocean, or possibly, as the planet, cycled through dry periods, two.

2. River beds and gullies indicate that water run, at least briefly, across the surface of mars.

3. At the marte vallies Channel, a very large amount of water would have flowed according to the estimates.

4. deposition of mud and clays can be observed on Mars by the Curiosity rover, just like on Earth, indicating presence of water in the past.