A welder orders argon gas and pure oxygen. The distributor requires a minimum order of $250. A cubic foot of argon gas costs $0.75 and a cubic foot of pure oxygen costs $0.50. To summarize the situation, the welder writes the inequality:

0.75a + 0.5p ≥ 250, where a is the number of cubic feet of argon gas and p is the number of cubic feet of pure oxygen.

Which graph's shaded region shows the possible combinations of argon gas and pure oxygen the welder can buy?

The figure shows triangle def and line segment bc, which is parallel to ef: triangle def has a point b on side de and point c on side df. the line bc is parallel to the line ef. part a: is triangle def similar to triangle dbc? explain using what you know about triangle similarity. part b: which line segment on triangle dbc corresponds to line segment ef? explain your answer. part c: which angle on triangle dbc corresponds to angle f? explain your answer. asap