What is the position of the centre of gravity of a:
(a) rectangular lamina
(b) cylinder?

Explanation

To determine the position of the center of gravity for a rectangular lamina and a cylinder, we can follow these steps:

### Step-by-Step Solution:

1. **Define Center of Gravity**:
- The center of gravity (CG) of an object is the average location of all the weight of the object. It is the point where the total weight of the body can be considered to act. This point is also referred to as the balance point of the object.

2. **Center of Gravity of a Rectangular Lamina**:
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