1. A 1.6-meter-long iron wire was wound around the red column of the ancient building, exceeding 0.03 meters twice. What is the radius of this cylinder?

[ 1.6-0.03]/2/2

= 1.3/4

=0.3925[ m]

2. The base of the sculpture is semicircular with a radius of 15m. It is planned to enclose it with stainless steel guardrail. How long is the stainless steel guardrail? How many square meters is this pedestal?

15*2 3. 14* 15*2/2

= 15*2 3. 14

= 15*5. 14

= 77. 1m

3. 14* 15* 15/2

=353.25 square meters

The diameter of the round flower bed is 20 meters. If a path 1 meter wide is built around the flower bed, what is the area of this path?

20/2 1*20/2 1*3. 14-20/2*20/2*3. 14

= 1 1* 1 1*3. 14- 10* 10*3. 14

=3. 14* 12 1- 100

=3. 14*2 1

=65.94 square meters

4. A trapezoid with an upper bottom of 8 cm and a lower bottom 12 cm, with a circle with a diameter of 8 cm in the middle. What is the area of the shaded part?

8 12*8/2

=80 square centimeters

3. 14*8/2*8/2

=50.24 square centimeters

80-50.24=29.76 cm2

5. A semicircular vegetable garden, 3 meters in diameter, how many square meters is the area of the vegetable garden?

3. 14*3/2*3/2/2

=3. 14* 1.5* 1.5/2

=3.5325 square meters

6. The radius of the circular lawn is 40m, and a cement road with a width of10m is built around the lawn. What is the area of this road?

3. 14*40 10*40 10-3. 14*40*40

=3. 14*50*50-3. 14*40*40

=3. 14*2500- 1600

=3. 14*900

=2926 square meters