Answer:
I think the answer is D a ray of violet light
Hope it helps!
Because there are so many different values of numbers, it would be impractical to use 1Ω, 2Ω, 3Ω... etc... Using colored bands helps make reading it a little easier to the trained eye. There are hundreds of thousands, if not tens of millions of different resistors would need to exist to cover every value. So you just use something called "preferred values" with their resistance values posted on them instead.
Method 1: gravimetry
advantages: Impurities in the sample can be identified
disadvantages: The process is long, because it goes through several stages
Method 2: titration
advantages: the process is fast, because the titrate and titrant react immediately
disadvantages: Sometimes the determination of the end point of the titration is carried out too fast or too slowly so that the calculations carried out are inaccurate
For 100m Race ,
displacement = distance covered .
divide the above equation by time t (assuming it takes t time to complete 100m race),
we get,
velocity = speed.
and for 400m race 1 lap is completed this means that racer's initial and final position coincide (or same) hence,
displacement = 0,
distance ≠0=400m.
=> displacement ≠distance.
=> velocity ≠ speed.