Can someone help me with this math homework please!

What are linear equations? could'ya explain too me, ? ! and how do you see what graph is a proportional relationship?

Alakefront cottage that is 30 feet high casts a shadow on the water. how long is that shadow if a 16-foot-high truck parked nearby casts an 8-foot shadow?

Un used xx milliliters, or 90\%90%, of his favorite bottle of hot sauce. which of the following expressions could represent the volume of a full bottle of jun's favorite hot sauce, in milliliters? choose 2 answers: choose 2 answers: (choice a) a \dfrac{x}{0.9} 0.9 x (choice b) b \dfrac{10}{9}x 9 10 x (choice c) c 0.9x0.9x (choice d) d xx (choice e) e x+0.1x+0.1