1. Draw the largest circle in a rectangle with a length of 6.5cm and a width of 4cm, mark the radius of the circle and calculate the area of the circle.
2. Divide a circle into 8 equal parts, if you cut it open; Can be converted into an approximate rectangle. Please draw an approximate rectangle after you put it together. If the circumference of the rectangle is 6 cm longer than the circumference of the circle, please calculate the circumference of the circle.
application problem
1. When the largest pyramid in Egypt was built, it was 147 meters high. Due to wind and rain erosion, it is now lower than when it was built 1/2 1. How many meters has this pyramid shrunk?
2. The sixth grade students of Lvyin Primary School took part in the physical education standard test, and the number of people who reached the standard increased from 282 to 376 now, an increase of a few percent?
The biggest river in the world is the Amazon River in South America, with a total length of 6,480 kilometers. The Yangtze River in China is the third largest river in the world, only about 3% shorter than the Amazon River. How many meters is the Yangtze River?
4. The volume decreases after hydration111. Now there is a piece of ice, which has a volume of 6.6 cubic decimeters after melting into water. What is the volume of this ice?
5. Uncle Wang kept the bonus of 10000 yuan in the bank for three years, with an interest rate of 3.24%. After the expiration of three years, after deducting 20% interest tax, will the interest earned be enough to buy a mobile phone with a price of 1000 yuan?
6. A bucket of water contains exactly 8 bottles in a large flask and 12 bottles in a small flask. If you take four full bottles of these two kinds of water and pour them into this empty bucket, what is the height of the water surface? How many bottles of water are left in a small flask to fill this bucket?
7. When the optical cable is laid between Party A and Party B, when the whole project is 4/7 completed, it is only more than 80 kilometers away from the midpoint. What is the total length of this cable?