To get the surface area of a sphere, we need to have the radius. We are given the circumference. The circumference formula is C=2πr. We need to solve for r.
23 = 2πr
r=3.66
The calculation for surface area is <span>A = 4πr^2.
</span>A = 4<span>π(3.66)^2
Solve for A.
A= 168 cm^2.</span>
Answer:
0.133 ml
Step-by-step explanation:
The two available solutions to be used in the mixture are a 70% solution and a 85% solution
.
x = volume of 70% solution
y = volume of 85% solution
y = 2 ml
Therefore;
0.7 x + 0.85(2) = 0.75(x+2)
0.7x + 1.7 = 0.75x + 1.5
multiply through by 10 to get rid of the decimals
7x + 17 = 7.5x +15
collecting and simplifying
-0.5 x = -0.2
divide both sides by -1.5
x = -0.2/-1.5
x = <u>2/15 ml or 0.1333 ml</u>
According to the problem, there has to be 22 of them.
66/3=22
Hope it helps!
