Answer:
B.
Step-by-step explanation:
Perpendicular lines always intercept at a right angle (90 degrees).
You can eliminate 81 because we know 
The dot is on approximately 9.32 (my estimate) so I would square that number:
(9.32)² = 86.8624 so if you round this you get 87
I think your answer is gonna be 20
385 + 326 + 298 = 1,009 / 3 = 336.33
385 + 326 + 298 + x = 350
350 x 4 = 1,400
1,400 - 1,009 = 391
385 + 326 + 298 + 391 = 1,400 / 4 = 350
The answer is $391
8, 8 2/7, 26/3, 8.8
(You have to change 8 2/7 to 8.28 and 26/3 to 8.66