Question

how is migration responsible for the change in size of population

Answer 1

Of course migration is an important factor in changing the influx of population in various countries..People who migarate to another country reduce the population of their own country and increase the migration rate in other countries..Vice versa..

Answer 2

$\huge\mathfrak\green{ᴀɴsᴡᴇʀ}$

ᴍɪɢʀᴀᴛɪᴏɴ ɪs ᴀɴ ɪᴍᴘᴏʀᴛᴀɴᴛ ᴅᴇᴛᴇʀᴍɪɴᴀɴᴛ ᴏғ ᴘᴏᴘᴜʟᴀᴛɪᴏɴ ᴄʜᴀɴɢᴇ ʙᴇᴄᴀᴜsᴇ ɪᴛ ᴄʜᴀɴɢᴇs ᴛʜᴇ ᴅᴇᴍᴏɢʀᴀᴘʜɪᴄs ᴏғ ᴀ ᴄᴏᴜɴᴛʀʏ.