When a hypothetical diatomic molecule having atoms 0.8860 nm apart undergoes a rotational transition from the I= 2 state to the next lower state, it gives up a photon having energy 8.850x10⁻⁴ev. When the molecule undergoes a vibrational transition from one energy state to the next lower energy state, it gives up 0.2560 eV . Find the force constant of this molecule.