Answer:
21 r16
Step-by-step explanation:
All the choices are correct.
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In our base-10 number system, moving a digit one place to the left multiplies its value by 10. Moving it one place to the right multiplies its value by 1/10.
You know already that 1,000 has 10 times the value of 100, and 1/10 the value of 10,000.
First one b ≤ 9 good luck
Simple, the area is 80*50, 80*50=4,000 ft², the backyard has a dimension of 50*40=2,000 ft², subtract 4,000 from 2,000, 4,000-2,000=2,000 ft²