18. How many degrees does the minute hand turn in a minute? The hour hand?
$\Delta$ In one hour, the minute hand makes a full revolution, and in half an hour, it turns by $180^{\circ}$ (a straight angle). Half an hour is 30 minutes, so in one minute, it turns by $1 / 30$ of the angle in $180^{\circ}$, which is $180 / 30=6^{\circ}$.

The hour hand moves $1 / 12$ of a circle in one hour, meaning it moves 12 times slower than the minute hand. In one minute, it turns by $0.5^{\circ} . \triangleleft$