Can an old river go back to a youthful river? if so how?

Well . . .the river eventually end up in the ocean.

After that, the sun will cause the water to evaporate into cloud.

And eventually , the cloud will condense and fall down to the surface as rains, which eventually came back to the youthful river.

The answer to your is is c motion and shape

0 = 0.40 / 0 = 0

= 0.20 = 9.80 ⁄2 =?

=0 , = = 0.20 =0.50 0 0.40 ⁄

=0−122 =0−12(9.80 ⁄2)(0.50)2 =1.2