viet bang cah liet ke cac phan tu cua cac tap hop sau:
a) tap hop A cac so tu nhien co 2chu so ma chu so hang chuc lon hon chu so 3
b) tap hop B cac so tu nhien co 2 chu so ma chu so hang don vi gap doi hang chuc
c) tap hop C cac so tu nhien co 2 chu so ma trong so do co it nhat 1 chu so 4