Pardon most nearly means:

Miriam bought five cases of motor oil on sale. A case of motor oil normally costs $24.00, but she was able to purchase the oil for $22.50 a case. How much money did Miriam save on her entire purchase?

If the electrolyte solution in a battery is too low, you should add:

Leukemia is a blood disease in which white blood cells in the blood or bone marrow reproduce rapidly, interfering with the body's ability to produce red blood cells. Red blood cells are needed to perform vital bodily functions.
According to this passage:

Determine which of the choices best solves the problem shown in the first picture and then mark the corresponding choice on your answer sheet. The problem is presented in the first drawing and the remaining four drawings are possible solutions.