The number of planks of dimensions (4 m × 50 cm × 20 cm) that can be stored in a pit which is 16 m long, 12 m wide and 4 m deep is

1. 1900

2. 1920

3. 1800

4. 1840

Consider the following two statements:

Statement 1: If the circumference of a circle is 10π cm, then its area is 25π cm².

Statement 2: The area of a circle is π times its circumference.

Which of the following is valid?

1. Both the statements are true.

2. Both the statements are false.

3. Statement 1 is true, and Statement 2 is false.

4. Statement 1 is false, and Statement 2 is true.

Assertion (A): Heron's formula can be used to find the area of a scalene triangle only.

Reason (R): If ABC is a triangle with side a, b and c respectively, then its area = $\sqrt{s(s - a)(s - b)(s - c)}$, where s = $\dfrac{a + b + c}{2}$.

1. Assertion (A) is true, Reason (R) is false.

2. Assertion (A) is false, Reason (R) is true.

3. Both Assertion (A) and Reason (R) are true, and Reason (R) is the correct reason for Assertion (A).

4. Both Assertion (A) and Reason (R) are true, but Reason (R) is not the correct reason (or explanation) for Assertion (A).

Assertion (A): The volume of a cuboid having length, breadth and diagonal as 4 m, 3 m and 13 m is 144 m³.

Reason (R): Length of diagonal of a cuboid is $\sqrt{l^2 + b^2 + h^2}$.

1. Assertion (A) is true, Reason (R) is false.

2. Assertion (A) is false, Reason (R) is true.

3. Both Assertion (A) and Reason (R) are true, and Reason (R) is the correct reason for Assertion (A).

4. Both Assertion (A) and Reason (R) are true, but Reason (R) is not the correct reason (or explanation) for Assertion (A).