Street garden to build a circular flower bed, perimeter is 31.4 meters, in the flower bed around the construction of a 1 meter wide circular path. How much area of this path?
Inner radius 31.4 △ 3.14 △ 2 = 5m
Outer radius 5 + 1 = 6M
Area 3.14 × (6 × 6-5 × 5)
=3.14×11
=34.54 square meters
RELATED INFORMATIONS
- 1. This pair of_____ made of _____ How to fill in (glass)
- 2. 1. In the triangle ABC, if Sina - the absolute value of half + (the root of two-thirds 3-cosb) 178; = 0, find the angle C 2. In the triangle ABC, if Sina - the absolute value of 2 / 2 radical 3 + (3 / 3 radical 3-tanb) 178; = 0, find the angle C Angle A and angle B are acute angles
- 3. What are the advantages of the verb past double + ed
- 4. Given that the value of the algebraic formula (4x2 + ax-y + 6) - (2bx2-2x + 5y-1) has nothing to do with the value of the letter X, find the algebraic formula 3 (a2-2ab-b2) - (4a2 + a)
- 5. If the value of (2x2 + ax-y + 6) - 2 (bx2-3x + 5y-1) has nothing to do with the value of X, find the value of - 3 (A2 + 2ab-b2) - (4a2-5ab + B2)
- 6. If the value of polynomial (2 * x's square + ax-y + 6) - (2B * x's Square - 3x + 5y-1) has nothing to do with the value of letter X, find polynomial 3 (A's Square - 2ab-b's Square) We should use the ideas of junior one students! , find the value of polynomial 3 (the square of a - the square of 2ab-b) - (the square of 4 * a + the square of AB + b)
- 7. ② Given that the value of the algebraic formula 2 (x2 + ax-y) - 2 (bx2 + 3x) - 5y-1 has nothing to do with the value of the letter X, we can find the value of 2 (a3-2b2-1) - 3 (a3-2b2-1)
- 8. It is known that AB is opposite to each other, CD is reciprocal to each other, and the absolute value of X is equal to 2. Find the value of formula (a + B + CD) △ X
- 9. When x takes what value, the difference between 2X-4 and 2x + 1 is positive?
- 10. (1) Given a = 3, B = 1, find the values of A2 + 2Ab + B2 and (a + b) 2; (2) please take another set of values of a and B and calculate the values of the algebraic expressions A2 + 2Ab + B2 and (a + b) 2. What conclusions can you draw from the calculation results?
- 11. Plant the seeds in the soil
- 12. As shown in the figure, in △ ABC, ab = AC = 12cm, De is the vertical bisector of AB, intersecting AB, AC at D and e respectively. (1) if ∠ C = 70 °, calculate the degree of ∠ BEC; (2) if the perimeter of △ ABC is 30cm, calculate the perimeter of △ BCE
- 13. Are two-part words like binoculars plural or singular?
- 14. In triangle ABC, de ∥ BC ad: DB = 2:1, if the area of trapezoidal dbec is 10cm, the area of triangle ABC can be obtained
- 15. English translation What was the girl doing when she was hit by a car The teacher spent the whole weekend grading the children's papers 3. Miss Lin came to the library to collect information for her thesis He is always ready to help his classmates review their lessons Boys like playing football more than girls 6. Many companies are suffering from a lack of skilled workers The bomb exploded in the crowded street
- 16. Given that the square of a plus a minus 1 equals 200, then the value of one third of a's Square plus one third of a plus 333 is
- 17. When is bamboo a countable noun and an uncountable noun?
- 18. What's the simplest fraction of a fraction that expands its numerator by four times and reduces its denominator by four times, which is equal to 24
- 19. 1. A pair of mainly refers to "a pair; a pair", which is composed of two parts______ Number form______ It can be singular or plural 2. When the phrase "... A pair (s) of" is used as the subject, the singular and plural forms of the predicate verb should be written in Chinese______ The singular and the plural of 3. The nouns after a pair of can be modified with adjectives, which are often placed before pair________ . This pair of jeans is very good This _____ ______ ______ ______ very good. These two new soft sports shoes are my uncle's The ______ ______ ______ _______ _______ _______ my uncle's.
- 20. UFO, PM, cm, am, USA, CCTV, PRC, WTO, MTV, UK