Question

बारकोड स्कैनर आर द एग्जांपल ऑफ विच यूनिट ऑफ कंप्यूटर​

Answer 1

Placoid scales are found in sharks and rays, and can vary greatly in external appearance. Unlike the scales of bony fishes, placoid scales do not increase in size as the fish grows, instead new scales are added between older scales. Placoid scales are often referred to as denticles.

https://australian.museum › fishes

Placoid scales - The Australian Museum