first one c=50 50=2pir 25=pir 25/pi=r SA=4pir^2 SA=4pi(25/pi)^2 SA=4pi625/(pi^2) SA=2500/pi SA=795.8 D
2nd euqtion V=2254pi (4/3)pir^3=2254pi divide both sides by pi (4/3)r^3=2254 ties both sides by 3/4 r^3=1690.5 cube root both sides r=11.9126 SA=4pir^2 SA=4pi11.9126^2 SA=4pi141.909 SA=567.636pi SA=1783.3 D is answer
3rd find side legnth cube root each since V=side^3 volume 729 to 6859 is side legnths 9 to 19 every 9 units turns to 19
