Seismic question

The one with the higher mass on level three is worse.

Assuming the building as an SDF vibration for simplicity:

The period of the building will moderately increase due to the reduction of K, $$K=P/delta $$ By moving mas from 2nd floor to 3rd floor we increase deflection by roughly 1.2 hence decreasing the K by 1/5.

Natural frquency $ omega_n=sqrtfrac{K}{m} tau= 2pi/omega_n $ decreases moderately (0.04) which is good but it can not make up for the increase in the additional overturning moment by 150% and extra shear due to triangular sheer distribution.