Given that, a sphere has a surface area of about 999 square millimeters.
Formula to find the surface area of sphere is,
S= 4πr² Where r = radius of the sphere and S= surface area.
Given S= 999 square millimeters.
So, we can write:
4πr² = 999
4 * 3.14 * r² = 999 Since, π = 3.14
12.56 *r² = 999
Divide each sides by 12.56.
r² = 79.53821656
r = √79.53821656 Taking square root to each sides of equation.
r = 8.918420071
So, r = 8.918 Rounded to nearest thousandth.
So, radius of the sphere is 8.918 millimeters.
Hope this helps you!
Surface area of box=1200 cm²
<span>Volume of box=s²h </span>
<span>s = side of square base </span>
<span>h = height of box </span>
<span>S.A. = s² + 4sh </span>
<span>S.A. = surface area or 1200 cm², s²
= the square base, and 4sh = the four 'walls' of the box. </span>
<span>1200 = s² + 4sh </span>
<span>1200 - s² = 4sh </span>
<span>(1200 - s²)/(4s) = h </span>
<span>v(s) = s²((1200 - s²)/(4s)) </span>
<span>v(s) = s(1200 - s²)/4 . </span>
<span>v(s) = 300s - (1/4)s^3</span>
by derivating
<span>v'(s) = 300 - (3/4)s² </span>
<span>0 = 300 - (3/4)s² </span>
<span>-300 = (-3/4)s² </span>
<span>400 = s² </span>
<span>s = -20 and 20. </span>
again derivating
<span>v"(s) = -(3/2)s </span>
<span>v"(-20) = -(3/2)(-20) </span>
<span>v"(-20) = 30 </span>
<span>v"(20) = -(3/2)(20) </span>
<span>v"(20) = -30 </span>
<span>v(s) = 300s - (1/4)s^3 </span>
<span>v(s) = 300(20) - (1/4)(20)^3 </span>
<span>v(s) = 6000 - (1/4)(8000) </span>
<span>v = 6000 - 2000
v=4000</span>
Answer:
The answer is 54.
Step-by-step explanation:
54 divided by 2 will give you 27.
54 divided by 9 will give you 6.
So, 4 x 3 is 12, so 4 blades cost 79.74 x 3 (because every turbine has 3 blades each) is 318.96
