Answer: Avoid spilling of chemicals
Explanation:
The chemicals should be kept in air tight containers in order so that they cannot get spill over each other.
Cross contamination takes place when a different type of substance comes in contact with the different kind of substance.
The chemicals should be kept in a way that it does not comes in contact with the different one and get spoiled.
In the first class lever the fulcrum is located between the effort and the resistance.In second class lever The second class of lever has the fulcrum at one end, the effort applied at the other end, and the resistance somewhere between those points. [ The third class of levers has the fulcrum at one end of the lever, and the weight or resistance to be overcome is at the other end, with the effort applied at some point between. ]
I would say c but I would have to read your text book to be able to answer it accurately
