Answer
1800$^{\circ}$
Work Step by Step
1. We need to know number of rotations per second:
$\frac{600rot}{1min}$$\times$$\frac{1min}{60sec}$ = 10 rot/sec
2. Then how much rotations in 0.5 seconds
$\frac{1}{2}$sec$\times$$\frac{10rot}{1sec}$ = 5 rotations
3. As we know each rotation is 360$^{\circ}$, therefore we just need to multiply:
5rot$\times$$\frac{360^{\circ}}{1rot}$ = 1800$^{\circ}$
