Area of a Circle from Radius (with calculator)

This math topic focuses on calculating the area of a circle, given the radius, using the formula \( \pi \times \text{radius}^2 \). It involves solving problems with decimal and whole number results. The content is suitable for learners at an introductory level of circle area in geometry. Each question requires computation with a calculator, reinforcing skills in handling geometric formulas and the application of \( \pi \) in arithmetic operations.