A mechanical system model is derived as

\[\ddot{x}+2 \dot{x}+k x=10 \delta(t), \quad x(0)=0, \quad \dot{x}(0)=0\]

where \(k\) represents the coefficient of stiffness.

a. Find the response \(x(t)\) associated with \(k=2\) and \(k=4\).

b. 1 Plot the responses associated with \(k=2,4\) in the same graph by using the impulse command.