Answer:
49Pi cm^2
Step-by-step explanation:
Area of a circle = Pi r^2
Radius r = 7
Area = Pi x 7^2
= Pi x 7 x 7
= 49Pi cm^2

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Answer:
↝
Solution:




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If u evaluate it it will become
=5.996958256
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Explanation:
#Carry on learning
Answer:

Step-by-step explanation:
0.0057
first number
5
then the rest
7
equal
5.7
There's <u>three</u> zeros <u>behind</u> the number 5 which mean it will be -3

final answer

another example and it will be clear
0.0000403
first number
4
then the rest
03
equal
4.03
There's <u>five</u> zeros <u>behind</u> the number 4 which mean it will be -5

final answer

The amount of gold coating in millimeters needed for the ring is the difference between the total coating and the coating that has already been applied. From the given above, that would be,
0.03 mm - 0.021 mm = 0.009 mm
Thus, the answer to this question is letter B.