A 150-kg engine operates at \(1500 \mathrm{rpm}\).

(a) What percent isolation is achieved if the engine is mounted on four identical springs each of stiffness \(1.2 \times 10^{5} \mathrm{~N} / \mathrm{m}\) ?

(b) What percent isolation is achieved if the springs are in parallel with a viscous damper of damping coefficient \(1000 \mathrm{~N} \cdot \mathrm{s} / \mathrm{m}\) ?