Answer: 13 . 99 seconds
Explanation:
The formula to find how long it will take an object to rotate through 6.9 revolutions at an angular velocity is given as :
t = 2π x number of revolutions / angular velocity
Therefore :
t = 2π x 6.9 / 3.1
t = 2 x 3.142 x 6.9 / 3.1
t = 43.3596/3.1
t = 13. 98696774194
to the nearest tenth
t = 13. 99s