Answer:
In order for Ren who runs a harmburger stand and needed to clean up a season's worth of grease buildup, the cleaning product that he should look for that can handle a layer of grease would be those caustic chemicals. These caustic chemicals can be applied to break down the grease. When these grease are broken down, hot water can be applied to rinse it. These chemicals should be allowed to dwell on the surface of grease for a period of time to soften the grease buildup. Hope this answer helps.
Step-by-step explanation: