Why do some scientists think mars once had an extensive ocean where was it located?

Solve for r in the formula v = ir, when i = 5 and v = 15.

What did the pattern of earthquakes in the wadati-benioff seafloor zones show scientists? a.) earthquakes occur where the ocean floor reaches its highest temperatures. b.) many earthquakes take place 700 kilometers below the seafloor. c.) slabs of ocean floor return to the mantle in subduction zones. d.) ocean - trenches cause earthquakes.

Sarah is making a scale drawing of a painting that is 48inches wide by 120 inches high her paper is 12 inches wide and 24 inches tall she decides to use a scale 1 inches equals 4 inches is this a reasonable scale