if the diameter of the concentric circles as shown in the given figure are in the ratio 1:2:3 then find the ratio of the areas of three regions

1 : 4 : 9

Step-by-step explanation:

Given the ratio of diameters = a : b , then

ratio of areas = a² : b²

Here ratio of diameters = 1 : 2 : 3 , so

ratio of areas = 1² : 2² : 3² = 1 : 4 : 9

3< x< 5

step-by-step explanation:

|x - 4| < 1

there are two solutions, one positive and one negative.   remember to flip the inequality when taking the negative solution

x-4 < 1       x-4 > -1

add 4 to each side

x-4+4 < 1+4       x-4+4 > -1+4

x< 5                 x> 3

3< x< 5

i believe the answer is d.

hope it you! : d