168cm2
Let r cm be the radius of the balloon, then
<span>2pi(r)=23=>r=23/(2pi) </span>
<span>The surface area= </span>
<span>4pi(r^2)= </span>
<span>4pi[23/2pi)]^2= </span>
<span>(23^2)/pi=168.386 cm^2 </span>
<span>approximately.</span>
Hope this helps!! Ccccccccffffff
Let the original cost of laptop=x
Savings=20% = 20/100
Saved amount = $140
Original cost = saved amount * 1/savings
x = 140* 100/20
x = $7000
<span>4 cm / 1 year x 10 mm / 1 cm x 1 year / 365 days </span>
