Survey Sampling Methods/Theory Question based on 2 stage cluster sampling

Please solve all the questions below the image. Please no short cuts in any of the questions

There are 3 parts to this question and need solutions for all of them for 6 (b), (c), (d)

6 . ( 25 marks ) A psychologist wants to determine how many hours per week & - 10 year old boys in Toronto send playing video and computer games . To investigate this he randomly selects three Toronto elementary schools from the population of 230 elementary schools in Toronto , and then randomly selects twenty 20 ) 8 - 10 year old boys from each school . With the parents help , he has each of the sampled boys record their video and computer game time for a calendar week in hours . The results are presented in the following table School Number of Sample Sample Sample 8 - 10 year old boys size mean I standard deviation A 350 32 15 B 200 2 O 50 20 1 1