Statistics: Percentages from Groups

When the members of the Eye and I Photo Club discussed what type of film they had used during the past month, the following information was obtained; 77 used black and white film, 24 used only black and white, 65 used color, 18 used only color, 101 used black and white or color, 27 used infrared, 9 used all three types, and 8 didn't use any film during the past month.  
a) What percent of the members used only infrared film? and
b) What percent of the members used at least two of the types of film?