Answer:
52.5
Step-by-step explanation:
7.50 x 7
Answer:
351.68 cm^2
Step-by-step explanation:
We need to find the area of the frame itself. the radius of the inner circle is 12, but the frame has a radius of 4. You add 12 and 4 and you get 16. The formula for area of a circle is A=πr^2. So A= 3.14 x16^2. Then you have A= 3.14x 256 and you get 803.84. But we only want the area of the frame, so you have to get the area of the inner circle and subtract. You get A= 3.14 x 12^2. 3.14x144 is 452.16. 803.84-452.16 is 351.68. Hope this helped. :)
Answer:
top one
Step-by-step explanation:
i got it right :)
Mixing the two concentrations would give a new concentration which is in between 50 - 60% .
D. 63% cannot be obtained
