Question

the density of ozone in temperate regions (30°-60°) is (a) 250 DU, (b) 350 DU, (c) 450 DU

Answer 1

answer : option (b)

explanation :- actually, DU is known as Dobson unit to measure density of ozone in research.

usually, density of ozone (O3) is 250DU around equator and and about 450 DU in the subpolar regions during non-hole forming times.

but in temperature regions , density of ozone is the average of density around equator and density in the subpolar region during non- hole forming times.
so, density of ozone in temperate regions = (250 + 450)/2 = 350DU

hence, option (c) is correct.

Answer 2

Answer : $\bold{350 \: DU}$


Explanation -

The density of ozone in temperate regions (30° - 60°) is "350 DU"

The amount of total atmospheric ozone is measured in terms of "Dobson Units (DU)".

Generally, Dobson Units is used to measure the thickness of ozone layer.

One Dobson Unit is equivalent to a layer of ozone 0.01 mm thick at standard temperature.

Ozone concentrations in the tropics usually average 250 DU around the equator whereas in the subpolar regions usually 450 DU during non-hole forming times.

Density of ozone is the average of density around the equator and in the subpolar regions. Hence, 250 + 450 = 700/2 = 350 DU.