What is it called when a mistake “sneaks by” the proofreader in a dna molecule?

What is the maximum amount of al2(so4)3 which could be formed from 15.84 g of al and 12.89 g of cuso4?

There is one girl i like and i don't know how to tell her that, i have a feeling she knows but if she doesn't i don't want to make a fool out of myself how is one way to boost my confidence on asking her out

What rule is used to determine how many covalent bonds an element can form? a. the number of covalent bonds is equal to six c the number of covalent bonds is equal to five minus the group number plus the group number b. the number of covalent bonds is equal to eight d. none of the above minus the group number select the best answer from the choices provided