Questions

Mumbai has been ranked the world's second most densely populated city with 31,700 people per sq km, by the World Economic Forum (WEF) citing UN Habitat Data. Bangladesh's capital Dhaka topped the list with 44,500 people per sq km. Rajasthan's Kota has been ranked the world's seventh most densely populated city with 12,100 people per sq km.

From first figure : each fig has the value of 20 => It has inside 4 figures => Each individual figure has the value of '5'

From second => Each Triangle has the value of '1' (bcoz it contains two in each)

From third => Figure star has the value of '4'

Then in fourth => 4 + 1 + 15 = 20

In VIBGYOR. It has colors ordered from highest to lowest frequency.

              Violet > Indigo > Blue > Green > Yellow > Orange > Red

That says Violet has the highest frequency.

We know, Speed of light = Frequency x Wavelength

=> As frequeny is inversely proportional to wavelength i.e, as frequwncy goes high wavelength goes down.

So, the violet color has the highest frequency.