For anyone wondering (like me) what COP is in this context, it’s Coefficient of Performance: https://en.m.wikipedia.org/wiki/Coefficient_of_performance
That is, if you want to chill your cabbage to 4.3 degrees C, your room temp should be not more than 5.6 degree C. Or... if it's 25 degrees outside, in an ideal case your cabbage is 23.7 degrees cool.
Btw, max theoretical COP increases rapidly as T'hot - T'cold shrinks to zero. Your practical AC or fridge delta T is much more than that, depending on the weather.