The smallest division on main scale of a vernier caliper is `1 mm and 10` vernier divisions coincide with `9` main scale divisions. While measuring the length of a line, the zero mark of the vernier scale lies between `10.2 cm and 10.3 cm` and the third division of vernier scale coincides with a main scale division.
(a) Determine the least count of the caliper.
(b) Find the length of the line.

Explanation

To solve the problem step by step, we will break it down into two parts as per the question.

### Part (a): Determine the least count of the caliper.

**Step 1:** Identify the smallest division on the main scale.
- The smallest division on the main scale (MSD) is given as 1 mm.

**Step 2:** Determine the value of one Vernier scale division (VSD).
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