How is the empirical formula different than the molecular formula?

The empirical formula for a chemical compound is an expression of the relative abundances of the elements that form it. It isn't the same as the molecular formula, which tells you the actual number of atoms of each element present in a molecule of the compound. Different compounds with very different properties may have the same empirical formula.

the child will have heterozygous dominant chromosomes as characters of his father are dominant over the characters of his mother.

the child is heterozygous

i believe it is-

d.) gravity pulled particles of dust and gas together to form planets.