Assertion (A): The function ke^st with both σ and ω positive and s > 0 depicts a sinusoid whose amplitude increases with time.

Reason (R): If σ = 0, ke^st becomes a sinusoid.

1. To increase gain for weak signals
2. To decrease gain for strong signals
3. To change the contrast when we switch from one channel to other
4. To reduce flutter

1. 2 wattmeter
2. one wattmeter
3. 3 wattmeter