Greatest common factor for 16uv^8 and 28u^7v^2y^3

Which matrix multiplication is possible?

The appalachian trail is a hiking trail that passes through the appalachian mountains. three members of a teen hiking group hiked a section of the trail. the hikers stopped at a rest area and equally shared 3 4 gallon of water. how much water did each person get?

Consider the proof. given: segment ab is parallel to line de. prove: what is the missing statement in step 5?