The nurse is teaching a client about self-administration of insulin and about mixing regular and neutral protamine Hagedorn (NPH) insulin. Which information is important to include in the teaching plan?

When mixing insulin, the regular insulin is drawn up into the syringe first.

If two different types of insulin are ordered, they need to be given in separate injections.

There is no need to inject air into the bottle of insulin before withdrawing the insulin.

When mixing insulin, the NPH insulin is drawn up into the syringe first.