Answer: sqrt(2)/2 which is choice D
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Explanation
(3pi/4) radians converts to 135 degrees after multiplying by the conversion factor (180/pi).
The angle 135 degrees is in quadrant 2. We subtract the angle 135 from 180 to find the reference angle
180-135 = 45
Then you can use a 45-45-90 triangle to determine that the ratio of opposite over hypotenuse is sqrt(2)/2
sine is positive in quadrant 2
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Alternatively, you can use a unit circle. Refer to the diagram below. In red, I've circled the angle 3pi/4 radians. The terminal point for this angle has a y coordinate of sqrt(2)/2
Recall that y = sin(theta).
If the place to the right of where you are rounding is 5 or higher, you have to round up. If it is 4 or lower, you have to round down. In the hundreds place, there is a 4. That's lower than 5 meaning that you round down/stay. So, the nearest thousands place is 3,000.
D.36 60 .... because 6 times 6 is 36 and 6 times 10 is 60