The following images show four identical sun-like stars and their companion planets, all traveling in circular orbits. in each case, the mass of the planet is given in jupiter masses and the orbital distance is given in astronomical units (au). rank each case based on the strength of the gravitational force exerted by the extrasolar planet on its central star, from weakest to strongest. if you think that two (or more) diagrams should be ranked as equal, drag one on top of the other(s) to show this equality. (not to scale)

Ateam of astronauts is on a mission to land on and explore a large asteroid. in addition to collecting samples and performing experiments, one of their tasks is to demonstrate the concept of the escape speed by throwing rocks straight up at various initial speeds. with what minimum initial speed vesc will the rocks need to be thrown in order for them never to "fall" back to the asteroid? assume that the asteroid is approximately spherical, with an average density p 3.84 x108 g/m3 and volume v 2.17 x 1012 m3 recall that the universal gravitational constant is g 6.67 x 10-11 n m2/kg2

Need in all of themmm only answer if you know pls

Examine the equation. 23490th→23088ra+42he what kind of barrier would you need to block the radioactive particles from this reaction? a. a piece of paper b. a sheet of aluminum foil c. a two-inch block of lead d. a solid concrete block