A$.(3$pts$.)$Unpolarized sunlight with intensity I$0$is incident on the first filter. What is the intensity of the light coming out of the second filter?

B$.(2$pts$.)$A third polarizer is now added, also at $45$from the second polarizer. What is the intensity of the light coming out of the third polarizer?

C$.(2$pts$.)$Now the middle polarizer is removed $($and the other two remain unchanged$).$What is the final intensity of the light in this case?

D$.(3$pts$.)$Suppose we repeat the entire process in parts A$-$C above, but with polarizers at an angle of $30$from each other. What would the final intensity be in that case, after removing the middle polarizer?