Four device each with a gain of 10 db are connected in series if the out put power level is -40dbm determine the input power level in dbm?

Four device each with a gain of 10 db are connected in  series if the out put power level is -40dbm determine the input power level in dbm?

Given C=119pF and R=13.5mOhms determine upper cut off frequency?

An eeg signal proesses 10uV signal in the presene of 125uv noise. Calculate the processing signal gain and processed SNR mif signal averaging of repetition of the waveform is performed?