Ships arriving in US. ports are inspected by Customs ofcials for contaminated cargo. Assume, for a certain port, 20% of the ships arriving in the previous year contained cargo that was contaminated. A random selection of 70 ships in the current year included 7 that had contaminated cargo. Does the data suggest that the proportion of ships arriving in the port with contaminated cargoes has decreased in the current year? Use c1=.05 - Find the zstatistics phat -P p 1-p