按关键词阅读：
Problem 14 
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Answer: D
Solution:
even powers of 19 have a units digit of 1, and odd powers of 19 have a units digit of 9. So, 19^19 has a units digit of 9. Powers of 99 have the exact same property, so 99^99 also has a units digit of 9. 9+9=18 which has a units digit of 8.Problem 15
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Answer: C
Solution:
The large triangle ABC has sides of length 4. The medium triangle has sides of length 2. The small triangle has sides of length 1. There are 3 segment sizes, and all segments depicted are one of these lengths.
Starting at A and going clockwise, the perimeter is:
AB+BC+CD+DE+EF+FG+GA=4+4+2+2+1+1+1=15.Problem 16
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Answer: C
Solution:
The length L of the rectangle is 1000/25=40 meters. The perimeter is 1000/10=100 meters. So the width is 100/2-40=10 meters. Area is 40*10=400 .Problem 17
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Answer: A
Solution:
1@2=1*1/2=1/2; 1/2@3=(1/4)/3=1/12;
2@3=4/3；1@4/3=1/（4/3）=3/4；the answer is 1/12-3/4=-2/3.Problem 18
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Answer: E
Solution:
Area of quadrilateral I is : 1/2*1*1+1/2*1*1=1；
Area of quadrilateral II is : 1/2*1*1+1/2*1*1=1;
Perimeter of quadrilateral I is : 1+sqrt(2)+1+sqrt(1);
Perimeter of quadrilateral II is : sqrt(5)+sqrt(2)+1+sqrt(2)Problem 19
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Answer: C
Solution:
Draw line BD. Then draw CO, where o is the center of the semicircle. You have two quarter circles on top, and two quarter circle-sized "bites" on the bottom. Move the pieces from the top to fit in the bottom like a jigsaw puzzle. You now have a rectangle with length BD and height AO, which are equal to 10 and 5, respectively. Thus, the total area is 50.Problem 20
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Answer: A
Solution:
Problem 21
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稿源：(艾蕾特教育)
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标题：is：AMC8 -- 2000年真题解析，( 三 )
