Explain how the scales on some fishes can be used to estimate the age of those fishes

Amount of wear, and how long they are may contribute with age and maybe even coloration and pigment. 

Because the earth is not round ,but it may seem round when viewed from ,our planet but true some points earth is not round was an oblate spheroid -a square that it squashed as globe however is not even a perfect oblate spheroid.in fact isaac newton's first proposed that earth was not perfectly round but it was an oblate spheroid instead.that mean a square that is squashed as its poles and swollen at the