Give a definition for each of the following: Gully

Stream

Oxbow lake

Runoff

Delta

Fjord

Meander

Sea stack

Spit

From center station, a train departs every 30 minutes on the fast line and a train departs every 50 minutes on the state line. if two trains depart from center station at 8: 00 a. m., one on each of the two lines, what is the next time that two trains, one on each line, will depart at the same time?

Anybody wanna ? (picture included? )

Which accurately compares concave and convex lenses?