Could you help me answer these three True or False Geometry questions..?

True or False...





If the volume of a cube is 1000, the length of each of its edges is 10.





The area of a sphere equals 4pi times the cube of its radius.





Two right circular cones with radii 4 and 8, and heights 10 and 20, respectively, are similar.





Thanks so much in advance for helping!!Could you help me answer these three True or False Geometry questions..?
Hi,





TRUE


false


TRUE





If the volume of a cube is 1000, the length of each of its edges is 10.





V = e鲁


V = 10鲁


V = 1000 10 is correct so this is true.





The area of a sphere equals 4pi times the cube of its radius.





The surface area of a sphere is SA = 4蟺r虏 and its volume is 4/3蟺r鲁. The formula listed above is false.








Two right circular cones with radii 4 and 8, and heights 10 and 20, respectively, are similar





The corresponding parts have the same ratios so the figures are similar. 4/8 = 陆 and 10/20 = 陆. This statement was true.





I hope that helps!! :-)Could you help me answer these three True or False Geometry questions..?
1.) V = s^3


1000 = s^3 (cube root both sides)


(1000)^(1/3) = (s^3)^(1/3)


10 = s





True





2.) A of sphere = 4/3*pi*r^3





False





3.) 4/10 = 0.4, 8/20 = 0.4





True
I think:





True- definitely





False- 90% sure





True - 4/10 = 8/20
1st one is true