A nurse is providing discharge teaching to a client who has diabetes mellitus and a new prescription for regular and NPH insulin. Which of the following statements by the client indicates an understanding of the teaching?

"I will inject air into both vials before pulling up the insulins into the syringe."

"I will shake the insulin vials vigorously before drawing up the medication."

"I will draw up the NPH insulin first and then the regular insulin."

"I will insert the needle into my abdomen at a 15° angle."