A dog is pulling on a leash while walking down the sidewalk. What frame of reference would
indicate that the dog is not moving?
A. A nearby building
B. A tree
C. The leash
D. The sidewalk

I think, leash makes the most sense as an answer. Good luck.

Ifound this on google “your outer ear collects sound waves and reflects them into a tiny tube called the ear canal. at the end of the ear canal is a thin, skin-like membrane stretched tightly over the opening, called the eardrum.” i hope this you for what your looking for

Answer(b) both involve the use of levers;