Question

why do fish and frogs lay eggs in hundreds whereas Hen lay only one egg at a time

Answer 1

because they are different from hen Their eggs are are very very small in size

Answer 2

frozen fish lay so many eggs at time because they do not take care of them after the young most only few of them can survive to become idols and there is also a difference of fertilization fishes and frogs have external fertilization where the the baby comes out after the egg is out and in internal fertilization
all the fertilization occurs in the uterus of the Mother's body while in external fertilization fertilization occurs out of mother's body where she lay eggs



hope you understood my answer I have not copied it from anywhere I have told you this answer without anyone's help and its in my own language not from any book