1. The surface area of a sphere with a radius of 1 cm is 4π cm^2. Therefore, the surface area of a sphere with a radius of 3 cm would be 4π(3)^2 = 36π cm^2.
2. The surface area of a sphere with a radius of 20 cm is 4π(20)^2 = 1,600π cm^2. Therefore, the surface area of a sphere with a radius of 40 cm would be 4π(40)^2 = 1,600π cm^2.
3. The surface area of a sphere with a radius of 3.5 m is 4π(3.5)^2 = 153.94π m^2.
Therefore, the surface area of a sphere with a radius of 9 m would be 4π(9)^2 = 324π m^2.
4. The surface area of a sphere with a radius of 10 cm is 4π(10)^2 = 400π cm^2. Therefore, the surface area of a sphere with a radius of 20 cm would be 4π(20)^2 = 1,600π cm^2.
5. The surface area of a sphere with a radius of 6 cm is 4π(6)^2 = 144π cm^2. Therefore, the surface area of a sphere with a radius of 12 cm would be 4π(12)^2 = 576π cm^2.
Surface Area of Spheres Practice
1. 6
2. 1,600π
3. 162.78
4. 400π
5. 144π
2 answers
Finally some answers is correct 100% however, you have to put the pi symbol after a few of them.