You can multiply 256 by 3 to get your answer but the answer would be 768. If my answer is correct please make this a brainiest answer it would really help.
√ (1/144) = 1/12
Because √1 = 1 ; √144 = 12
⇒ C
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Answer: Choice B</h3>
Explanation:
Cosine is positive in quadrants I and IV, but quadrant IV isn't shaded in so we can rule out choice A.
Sine is positive in quadrants I and II. So far it looks like choice B could work. In fact, it's the answer because sin(pi/6) = 1/2 and sin(5pi/6) = 1/2. So if 0 ≤ sin(x) < 1/2, then we'd shade the region between theta = 0 and theta = pi/6; as well as the region from theta = 5pi/6 to theta = pi.
Choice C is ruled out because tangent is positive in quadrants I and III, but quadrant III isn't shaded.
Choice D is ruled out for similar reasoning as choice A. Recall that 
Because ABCD is a rectangle, the length of CD is 12 cm.
We need to determine the length of DE. If we can do that, then the sum of the lengths of CD and DE represents the unknown: the length of CE.
To find the length of CE, we have to "solve" the upper triangle.
Here's an outline of what to do:
1. Show that BC=AD and find the length.
2. Note that angle CAD is 60 degrees. Why?
3. Note that angle EAD is 30 degrees. Why?
4. Find the length of ED
5. Add ED and DC, that is, ED + 12 cm. This is your answer.
Please ask questions if need be.