Light Precedes Through Three Polarizing Sheets

Short Answer

Light precedes through three polarizing sheets. Unpolarized light enters the 1st sheet and the resultant vertically polarized beam continues through the 2nd and 3rd. The 2nd sheet has its transmission axis at 50.° with respect to the 1st, and the 3rd is at 70.° with respect to the 1st.
(a) What percent of the original intensity emerges from filter #1?
(b) What percent of the original intensity emerges from filter #2?
(c) What percent of the original intensity emerges from filter #3?
(d) If filter 2 has its transmission axis changed to 30.°, what % intensity now emerges from the 3rd filter?