1. The area of a circle with a radius of 3cm is () less than that of a circle with a radius of 4cm 2. How much more is 100g than 75g 3. 30 meters is one sixth shorter than () meters 4. Take a 10 meter long steel wire and wind it three times on a circular turntable, which is 0.58 meters more. Is the radius of the turntable () meters 5. When a commodity is sold at 70% discount, it is 6 yuan cheaper than the original price. The original price of this commodity is () yuan 6. In a rectangular paper with a length of 14.8cm and a width of 6.4cm, can you cut () circles with a radius of 1cm

1. The area of a circle with a radius of 3cm is () less than that of a circle with a radius of 4cm 2. How much more is 100g than 75g 3. 30 meters is one sixth shorter than () meters 4. Take a 10 meter long steel wire and wind it three times on a circular turntable, which is 0.58 meters more. Is the radius of the turntable () meters 5. When a commodity is sold at 70% discount, it is 6 yuan cheaper than the original price. The original price of this commodity is () yuan 6. In a rectangular paper with a length of 14.8cm and a width of 6.4cm, can you cut () circles with a radius of 1cm

1.(4^2-3^2)/4^2=43.75%
2.(100-75)/75=33.33%
3.30/(1-1/6)=36
4.3 * 2 * 3.14r + 0.58 = 10, r = 0.5
5.0.7 * x = X-6 leads to x = 20
6. The diameter of the circle is 2cm, the length can be cut 14.8/2 (rounded) = 7, and the width can be cut 6.4/2 (rounded) = 3; therefore, it should be able to cut 7 * 3 = 21

As shown in the figure, the four vertices of the quadrilateral ABCD are on ⊙ o, and the diagonals AC ⊥ BD, OE ⊥ BC are on E. prove that OE = 12ad

It is proved that: connect CO and extend cross ⊙ o to P, connect BP and AP, ∵ CP is diameter, ∵ PBC = ∠ PAC = 90 °, ∵ OE ⊥ BC, OE passes through the center O, ∵ be = CE, ∵ Po = OC, ∵ OE = 12bp,