Friis equation involves noise factor and gain, the expression is used to calculate the overall noise factor of a given cascaded system, for example a cascaded amplifier with many stages. below shows the expression for calculating the total noise factor using friis equation. Fn = F1 + (F2 - 1 / G1) + (F3 - 1 / G1G2) + (F4 - 1 / G1G2G3) ....... and so on Where: Fn = The total noise of all stages together F1 = The noise factor of stage 1 F2 = The noise factor of stage 2 F3 = The noise factor of stage 3 G = Gain of respective stage Friis equation involves noise factor and gain, the expression is used to calculate the overall noise factor of a given cascaded system, for example a cascaded amplifier with many stages. below shows the expression for calculating the total noise factor using friis equation. Fn = F1 + (F2 - 1 / G1) + (F3 - 1 / G1G2) + (F4 - 1 / G1G2G3) ....... and so on Where: Fn = The total noise of all stages together F1 = The noise factor of stage 1F2 = The noise factor of stage 2 F3 = The noise factor of stage 3 G = Gain of respective stage Friis equation involves noise factor and gain, the expression is used to calculate the overall noise factor of a given cascaded system, for example a cascaded amplifier with many stages. below shows the expression for calculating the total noise factor using friis equation. Fn = F1 + (F2 - 1 / G1) + (F3 - 1 / G1G2) + (F4 - 1 / G1G2G3) ....... and so on Where: Fn = The total noise of all stages together F1 = The noise factor of stage 1 F2 = The noise factor of stage 2 F3 = The noise factor of stage 3G = Gain of respective stage

Te=(Fn-1)To where To=290K so answer is 11.6K

This additive noise come from varies factors , one of the main factor is Temperature.Why this noise said to additive in the sense this noise only adding the signal not integrating the noise, so it is a cumulative processes, not integrating one.

Excess noises in communication refer to any factors that disrupt the clarity or effectiveness of a message being shared. This can include physical noise like loud environments, psychological noise such as preconceived biases or distractions, and semantic noise like language barriers or jargon. Addressing these noises is important for ensuring accurate and successful communication.

the bandwidth and the signal to noise ratio