G Let Y be a normal random variable with mean μ and variance σ2 . Assume that μ is known but σ2 is unknown. Show that ((Y-μ)/σ) 2 is a pivotal quantity. Use this pivotal quantity to derive a 1-α confidence interval for σ2 .

The graph shows the decibel measure for sounds depending on how many times as intense they are as the threshold of sound. noise in a quiet room is 500 times as intense as the threshold of sound. what is the decibel measurement for the quiet room? 20 decibels28 decibels200 decibels280 decibels