By definition, the speed of an object is given by:

Where,
dr/dt: derived from the position with respect to time
Therefore, speed has units of length over units of time.
Thus, speed is a derived quantity, since it depends on the value of two other quantities.
Answer:
a derived quantity is:
C. Speed
Answer:
(A) Total energy will be equal to 
(b) Energy density will be equal to 
Explanation:
We have given diameter of the plate d = 2 cm = 0.02 m
So area of the plate 
Distance between the plates d = 0.50 mm = 
Permitivity of free space 
Potential difference V =200 volt
Capacitance between the plate is equal to 
(a) Total energy stored in the capacitor is equal to


(b) Volume will be equal to
, here A is area and d is distance between plates

So energy density 
Answer:
8046.72 meters pretty sure
Its called the "westerly"