NASA has discovered a new planet that has an ocean. Using today’s technology, how would you propose studying that ocean, all that’s in it and the sea floor beneath it? Assume an unlimited budget.

only #2 represents an object at rest on a table.

in #1, there is no normal force due to the table; the object is accelerating downward.

in #3, the vertical forces are not balanced; the object is accelerating downward.

in #4, neither the vertical nor the horizontal forces are balanced. the object is accelerating upwards and to the right.