Answer:
Reference angle will be 30°
sin(330°) will be equal to 
cos(330°) will be equal to 0.866
Step-by-step explanation:
We have given angle is 330°
As the angle
is in forth quadrant
We know that in forth quadrant the reference angle is given by
Reference angle 
As the angle is 330°
So the reference angle will be 
Now we have to find the value of
sin(330°) 
And now 
Answer:
c
Step-by-step explanation:
Two sum of any two side lengths of a triangle will always be greater than the length of the remaining side
a doesn't work because 8+12=20 and 20 is not greater than 20
b doesn't work because 4+5=9 and 9<10
d doesn't work because 6+6=12 and 12 is not greater than 12
c is the only option where you can take any two sides, add them, and the sum will be greater than the remaining side.
For example, for c,
6+8=14, and 14>10
8+10=18, and 18>6
10+6=16, and 16>8
You can find the numerical part of the answer because it is the same on the right side.
For example:
¹ <<==== Regrouped
89
+
67
---------
146 <<=== I had to press space so I could position it.
So that also happens in subtraction, the left side can be found by doing the same steps in the right column.
For example:
67
- <<=== this time there was no regrouping
12
-------
55
It cant be converted into a mixed number because it has no whole.