The number of visitors P to a website in a given week over a 1-year period is given by P(t)=121+ (t-89) e 0.02t, where t is the week and 1st 52. a) Over what interval of time during the 1-year period is the number of visitors decreasing? b) Over what interval of time during the 1-year period is the number of visitors increasing? c) Find the critical point, and interpret its meaning.