sorry i have 2 more questions:

what happens when a contour line crosses a river:

stays flat, bends upstream , stops

why do contour lines never cross eachother:

they each represent a different elevation, the map would be too confusing, you cant tell the shape of the land

please help, these are my last questions

1 answer

http://academic.brooklyn.cuny.edu/geology/leveson/core/linksa/v_rule2.html

Your answer for the second question is correct.