Impulse response and convolution

Click on the correct answer for the following questions:

1. Stability of a system can be determined from its impulse response ?

true false

2. g(t) is the impulse response of a system. For the response y(t) on an arbitrary signal u(t) the following equations are valid:

3. g(t) and h(t) are the impulse and the step response of a system.

   Which relationship is valid:

4. The following electrical circuit can be described completely by a differential equation of

first order. circuit
second order.