1)
option A)
2)
option B) sample of 100
as sample size increases, margin of error decreases
3)
mean = 8
margin of error = z *sd/sqrt(n)
= 1.96* 5/sqrt(100)
= 0.98
hence
option E) 8 +-0.98 is correct
4)
n= ( z *sd/e)^2
= (1.96 * 100/25)^2
= 61.46
=62
option D)
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