Answer:
a) 8 pounds.
b) [26,42]
c)
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d) Weight above 42 pounds, so she cannot.
Explanation:
a. What is the margin of error?
Within 8 pounds, so margin of error of 8 pounds.
b. Express the acceptable weights as an interval.
34 - 8 = 26
34 + 8 = 42
[26,42]
c. Write an expression in the format to represent the interval.

d. Sally weighs 44 pounds. Can she play in the bounce house?
Weight above 42 pounds, so she cannot.