A study conducted by the Pew Research Center reported that 58% of cell phone owners used their phones inside a store for guidance on purchasing decisions. A sample of 15 cell phone owners is studied; a) What is the probability that six or more of them used their phones for guidance on purchasing decisions? b) What is the probability that fewer than ten of them used their phones for guidance on purchasing decision? c) What is the probability that exactly eight of them use their cell- phones for guidance on purchasing decisions?