During puberty, various changes occur in the body, including the development of facial features. While it is difficult to predict the exact changes that will occur in an individual, it is possible that the jawline may become more defined as a result of growth and maturation. However, the extent of these changes can vary from person to person due to factors such as genetics and hormonal influences.

Regarding the least count of a vernier caliper, the least count refers to the smallest measurement that can be read or measured using the instrument. The least count of a vernier caliper depends on its design and specifications. Typically, a standard vernier caliper has a least count of 0.02 mm or 0.001 inch. This means that it can measure distances or dimensions with an accuracy of 0.02 mm or 0.001 inch. However, there are also more precise vernier calipers available with smaller least counts for more precise measurements.