D none of the above
all of them is related to energy and motion , not to positioning.
The correct answer is “C” ultrasound. Hope this helps!
Answer:
b = 0.89
Explanation:
The given vector is, 
A is a unit vector
We need to find the value of b.
For a unit vector, |A| = 1
So,

So, th value of b is 0.89.
Answer:
a) -5.40 rad/s
b) -2.842 rad/s²
Explanation:
The direction is important in dealing with such questions. Clockwise is considered negative and counterclockwise is considered positive
a) Δω = final angular velocity - initial angular velocity
= -2.70 rad/s - 2.70 rad/s
= -5.40 rad/s
b) ∝ = Δω/Δt = (-5.40 rad/s)/1.90s = -2.842 rad/s²