Efficiency is completing a task as fast a possible the the least amount of effort.
The question ask to calculate and choose among the following is the distance of the microphone from the left - most speaker in order to pick up the loudest sound and the best answer would be letter C. I hope you are satisfied with my answer and feel free to ask for more if you have questions and further clarifications
Answer:
The helicopter was 1103.63 meters high when the package was dropped.
Explanation:
We consider positive speed as a downward movement
y: height (m)
t: time (s)
v₀: initial speed (m/s)
Δy = v₀t + 
gt²
Δy= 15
×15 s + ×9.81
×(15 s)²
Δy= 1103.63 m
Work = (force) x (distance) =
(200 N) x (3.5 m) = <em>700 joules</em>
