Final answer:
The area enclosed between concentric circles with radii 2.1 cm and 1.4 cm can be found by subtracting the smaller area from the larger area. It is approximately 7.683 cm².
Step-by-step explanation:
The area enclosed between concentric circles with radii 2.1 cm and 1.4 cm can be found by subtracting the smaller area from the larger area. The formula to find the area of a circle is A = πr², where A is the area and r is the radius.
For the larger circle with a radius of 2.1 cm, the area would be A = π(2.1 cm)². Plugging in the value gives us A = 4.41π cm².
For the smaller circle with a radius of 1.4 cm, the area would be A = π(1.4 cm)². Plugging in the value gives us A = 1.96π cm².
To find the area between the two circles, we subtract the area of the smaller circle from the area of the larger circle: (4.41π cm²) - (1.96π cm²) = 2.45π cm².
Using the approximate value of π as 3.14, we can calculate the approximate area: 2.45π cm² ≈ 7.683 cm².