6.20 There is a narrow population of readers who can read 5000 words over a 15-minute span with a standard deviation of 120 words. Over a period of a month, a sample of 50 of these readers is selected and asked to refrain from reading and only watch television. They are then asked to read again over a 15-minute period, and their word count X is recorded. To test Ho: p = 5000 versus H < 5000 with respect to television conditioning, the critical region X