#### Answer

$1280^{\circ}$

#### Work Step by Step

1.Given 320 rotations per minute, change it into degrees per minute by multiplying it by 360 degrees
$360\times 320=115200^{\circ}$per minute
2. Devide by 60 to find degrees per second
$115200 \div 60 = 1920^{\circ}$ per second
3. To find rotations in 2/3 of a second, multiply by factor 2/3
$1920\times\frac{2}{3} =1280^{\circ}$