You want to find the area of the circle. The formula for the area of a circle is A=πr^2 (Area=pi times radius squared). The diameter is the distance across the circle. Radius is half the diameter. Diameter=3. 3 divided by 2 equals 1.5. So, plug it into the equation. A=π1.5^2 (Area=pi times 1.5 squared).
Answer: See Below
<u>Step-by-step explanation:</u>
NOTE: You need the Unit Circle to answer these (attached)
5) cos (t) = 1
Where on the Unit Circle does cos = 1?
Answer: at 0π (0°) and all rotations of 2π (360°)
In radians: t = 0π + 2πn
In degrees: t = 0° + 360n
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Where on the Unit Circle does
<em>Hint: sin is only positive in Quadrants I and II</em>


In degrees: t = 30° + 360n and 150° + 360n
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Where on the Unit Circle does 
<em>Hint: sin and cos are only opposite signs in Quadrants II and IV</em>


In degrees: t = 120° + 360n and 300° + 360n