Draw a quick picture 143 divided by 11 equals 13

U would draw out 143 by drawing a box, then one stick at the bottom, then three sticks at the right side of the box. You would also have three small circles where the lines intersect... I am not good at explaining, but i hope i helped u a little bit

Aand b are correctly balanced reactions. they have the same number of atoms in both sides of the reaction