Answer:
a) 
b) 
Step-by-step explanation:
From the question we are told that:
3 coin are tossed
Therefore
Sample space 
Generally the sets that correspond with the result of at most one tail is therefore given as follows
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Therefore
The result is at most one tail when
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The answer would be: D-100. The reasoning of this is because if you take 3 X 10 to the third power and did the exponent (10 to the third power in this case) and multiplied it you would obviously get 1,000 for an answer. Then would would do 1,000 X 3 to get 3,000.
Sheila is incorrect! I think what she did is think the 38 was actually a 35, which WOULD of made her statement true, but since it's 38, she's very incorrect. Sheila should be using the quotient for the size of each piece. 38 divided by 5 is 7.6. The correct answer is 7.6 inches.