A child with type 1 diabetes mellitus develops diabetic ketoacidosis and receives a continuous insulin infusion. Which condition represents the greatest risk for this child

A. Hypercalcemia.
B. Hyperphosphatemia.
C. Hypokalemia.
D. Hypernatremi

在实验室中，配制500g0.9%的生理盐水：

（1）该实验必备的仪器有托盘天平、药匙、胶头滴管、量筒、细口瓶、烧杯和     ；

（2）该实验的主要步骤有计算、       、溶解、装瓶并贴标签。