I think its b but i am not surely sure so you might want to check with someone else
Both triangles that are given (with right angles) lie in plane m, proving that AC is perpendicular to plane m. As angle acd is from a triangle that shares the common perpendicular, it too is a right angle
13. Is 18
15. Is 86
17 is 5
19 is 15
21 is 24
23 is 29
Answer:
5
Step-by-step explanation: