*note: my previous thread will be deleted because I didn't include relevant equations + I put two unrelated problems in the same thread. 1. The problem statement, all variables and given/known data A cat bobble head doll consists of a weighted head on top of a spring. When the head hangs straight sown in equilibrium, it is observed that the spring stretches 2cm. When the head is displaced upward by 1 cm, it is observed to oscillate with a frequency of 3 Hz. a) Find the spring constant of the bobble head b) Find the mass of the bobble head 2. Relevant equations T = 2pi square root (m/k) 3. The attempt at a solution I tried to use the formula T = 2pi square root(m/k) to find m and k but I cannot use this because the mass and k are not given.