This shows an obivious figure- ground relationship as you can point out that the tree is the figure.

here I see a obvious fig./ground relationship, because the main focus is the ball.

This is is an obvious figure ground relate. because the tree is the focus.

This seems like an ambiguous figure and ground relationship because you can’t tell whether the cars or the building is the focus.

This ambiguous because the focus is between the car and the building next to it.

this photo I believe is ambiguous to a certain degree because the statue head should be the focus but there’s another dominant object nearby.