Below, express the reference angle $\theta'$ in the same units (degrees or radians) as $\theta$. You can enter arithmetic expressions like 210-180 or 3.5-pi.
The reference angle of $30^\circ$ is ${}^\circ$.
The reference angle of $-30^\circ$ is ${}^\circ$.
The reference angle of $1,000,000^\circ$ is ${}^\circ$.
The reference angle of $100$ is .
Hint: Draw the angle. The Figures on page 314 of the textbook may be helpful. To see the angle $1,000,000^\circ$ subtract a suitable multiple of $360^\circ$. To see the angle $100$, subtract a suitable multiple of $2\pi$.