Thanks to social media, the happiest creature on earth, an always smiling Australian marsupial called a quokka, has become well known. Suppose that the weights of quokkas can be described by the Normal model N(12,2.9 ). Complete parts a through c. a) What percent of quokkas weigh over 16.8 pounds? b) What percent of quokkas weigh under 13.8 pounds? c) What percent of quokkas weigh between 13.8 and 16.8 pounds?