Answer:
5.48 lb
Step-by-step explanation:
12 inches is 1 foot.
12.8 times that length will have 12.8 times that weight:
12.8 · 0.428 lb = 5.4784 lb ≈ 5.48 lb
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The given values have 3 significant figures, so the answer needs to be rounded to 3 significant figures.