Sorry for not posting a question earlier, here is my answer to the current question.
4 pieces(not including the packet of gum found in Cassie's hand when she was rescued in the lake)
Greg- outside in the yard next to the house
Greg- in Mark Horvatins car
Sara- on the boat
Sara- steps on it when she is on the dock
Yay!
O.k. here is mine:
In 4x4 Paul Charles had a disease which was caused by exposure to a type of mold. What was this disease called and what was the name of the mold that caused it?