Suppose that a market research firm is hired to estimate the percent of adults living in city A and city B who support Mark to be governor. 150 adult residents and 400 adult residents are randomly selected from city A and city B respectively. For city A, of the 150 people sampled, 90 responded yes; and for city B, out of 400 responded, 280 responded yes. Let and respectively denote the true proportions of adults living in city A and city B who support Mark