b) Triangle C is equilateral and has side length \( x \mathrm{~cm} \). The ratio of the perimeter of rectangle A to the perimeter of triangle C is \( 5: 4 \). Work out the value of \( x \).

A rectangular prism has a length of 5 cm, a width of 3 cm, and a height of 4 cm. Calculate its volume.

A rectangular prism has dimensions of length 5 meters, width 3 meters, and height 2 meters. Calculate the volume of the prism.

61. A fountain pen with a cylindrical barrel of diameter 2 cm and height 10.5 cm , filled with ink, can write 3300 words. How many words can be written with that pen using 100 ml of ink? (Take \( 1 \mathrm{cc}=1 \mathrm{ml} \) ) \( \begin{array}{ll}\text { (a) } 40,000 & \text { (b) } 30,000\end{array} \)

5.3. A diameter and a chord, which is equal to the radius, are passed from the given point of the circle. Find the angle between them.

5.3. A diameter and a chord, which is equal to the radius, are passed from the given point of the circle. Find the angle between them.