Q: "A family standing on a mountaintop." Does this mean that "A family is outside."?
A: yes

Q: "A man rides a skateboard down the railing of a staircase in front of a closed storefront, with three people watching him." Does this mean that "The man is caucasian."?
A: it is not possible to tell

Q: "Two girls are looking into their own microscope." Does this mean that "two girls share a microscope"?
A: yes

Q: "Uniformed police officer guards a corner." Does this mean that "The officer is guarding the tower."?
A:
yes