1、求阴影部分的周长
先看图分析：阴影周长S＝半圆周L1+扇形的弧L2+扇形的一条半径R
计算：半圆直径＝扇形的半径＝60cm，扇形的圆心角＝45度
L1＝30π cm
L2=2π*60*(45/360)=15π cm
R=60cm
S=45π+60 (cm)
2、一个圆口水缸，从缸口量得它的内直径是54dm，缸壁厚3cm。现要用铁皮给它制作一个缸盖，使其正好盖住缸口的
从题目可以看出鱼缸的外直径是546cm (540+2*3), 所以半径是273cm ,所以其面积是 3.14*273*273
3、条件如下图，求阴影部分面积
∵大小矩形相似,小矩形长为x ；小矩形宽为60-20=40cm
∴60/40=﹙30＋x﹚/x
x=60cm
S阴影=60×﹙60＋30－40﹚=3000 c㎡
4、如果扇形的面积为60CM,当他的半径和圆心角各为多少时,扇形面积最大,并求最大值
设半径为r，则
弧长为60-2r 弧形角度/360度=弧长/圆周长=（60-2r)/(2πr)
弧形面积=πr²*（60-2r)/(2πr)=30r-r²=-（r-15）²+225
所以 r=15 时 弧形的最大面积225平方厘米
圆心角=360*(60-2r)/(2πr)=360(60-30)/(30π)=360/π 度时它的面积最大为225平方厘米
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如果有其他问题请另发或点击向我求助，答题不易，请谅解，谢谢。
祝学习进步！
5、求无版权信息的cms
无版权信息的CMS没有，而且，一般免费版的，未经过许可随意删除版权信息，那是侵权的，除非CMS开发者允许修改。而且修改那很简单，连着都懒得弄，还做什么网站？
6、collar measurement B/hole to button hole是什么意思 half bottom hip 60cms down是什么意思
白领测量的B /孔按钮孔
半底部髋60cms下降
7、麻烦解决下。谢谢
S小＝4×π×15＝2826cm
G平均＝56.52÷2826＝0.02g／cm
R大＝4×15＝60cm
S大＝4×π×60＝45216cm
G大球＝45216×0.02＝904.32g
8、求求了。
梯形的高：（160-40）/2=60cm
s=(40+100)*60=8400平方厘米
9、TOP10大左脚将,谁有谁?
10. Antonio Cabrini卡布里尼
One of the greatest left-backs the Italian game has ever seen, Cabrini joined Juventus from Atalanta in 1976 and spent over a decade in Turin. Equipped with the most elegant left foot, he won 73 caps for his country, scoring nine goals. However, that foot did let him down from the penalty spot in the ’82 World Cup Final.
9. Gheorge Hagi哈吉
The Romanian international helped Brescia into Serie A with a left foot that was one of the most deadly in world football. His 40-yard lob against Colombia in the 1994 World Cup has passed into legend.
8. Zico济科
The Brazilian ace was one of Serie A’s best players in the 80s and in two years with Udinese scored an amazing 22 goals in 39 games from midfield. The archetypal No 10 had a fabulous repertoire of unbelievable bicycle-kicks and a speciality in the thunderbolt volley.
7. Sinisa Mihajlovic 米哈伊洛维奇
The Serbian’s glorious hat-trick of free-kicks in 1998 for Lazio against former club Sampdoria symbolised the power of Serie A’s greatest ever dead-ball striker. In April 2006 he also scored his 27th top-flight free-kick goal – an absolute record.
6. Beppe Signori西格洛里
A pacey hitman who scored 107 goals in 152 games for Lazio in the mid 90s. His trick was using boots one size too small in the belief that it improved his touch and accuracy. It clearly worked as he was Capocannoniere on three occasions.
5. Christian Vieri维埃里
Always the focal point of any team’s attack, it seemed as though his left leg swung in slow motion but the resulting shot was usually as accurate as an Exocet missile. While playing for Inter he scored 103 goals in just 144 games. Deadly with his left foot, dire with his right.
4. Roberto Carlos卡洛斯
The former Inter left-back had the speed of his left-foot shots clocked at an unbelievable 170kph. The bulk of that power came from his incredible thigh muscles which measured a phenomenal 60cms in circumference.
3. Gigi Riva里瓦
Cagliari’s Rombo di Tuono – Roll of Thunder – possessed a legendary left foot and it helped him score a fabulous 164 goals in 315 games. He was Serie A Capocannoniere in 1970 and also top scorer for the Azzurri with 35 goals in just 42 games. He is said to have once broken a boy’s arm with that notorious left-footed shot of his. Ouch!
2. Giacinto Facchetti法切蒂
The symbol of Il Grande Inter was an overlapping full-back before they were generally recognised as such. His dynamic left peg scored some crucial goals and his crossing from the left wing made many more.
1. Diego Maradona马拉多纳
Napoli legend Diego Maradona scored 353 goals in his career and no less than 320 came with that infamous left foot of his. No ‘keeper was safe from his one-step run up and he scored goal after goal from a dead-ball.
10、半径为30厘米,弧长为60厘米,面积是多少
圆心角是 360º×60÷﹙2π×30﹚＝360º／π
面积是 π×30²×﹙360º／π﹚÷360º＝900平方厘米
面积是900平方厘米。