Obtain the time response y(t) for the following system: a -0.5, b - 5, 15k, 8(1-8), 0, u, where u(t) is a unit step occurring at t.
a. y(t) = -0.5e(-5t)u(t)
b. y(t) = 0.5e(5t)u(t)
c. y(t) = -0.5e(5t)u(t)
d. y(t) = 0.5e(-5t)u(t)