The radioisotope ra-224 decays by  emission to the ground state of rn-220 (94% probability) and to the first excited state of 0.241 mev above the ground state (5.5%). what are the energies of the two  particles?

Suppose that three astronomical objects, 1, 2, and 3 are observed to lie on a line, and the distance from object 1 to object 3 is d. object 1 has four times the mass of object 3, and seven times the mass of object 2. find the distance between objects 1 and 2 for which the net force on object 2 is zero.