Melissa buys an iPhone for $240 and gets consumer surplus of $160. What is her willingness to pay?

Asap! i'm not good math and i'm lost.

Describe the symmetry of the figure. identify lines of symmetry, if any. find the angle and the order of any rotational symmetry.

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