I know about marketing for the domestic market , different types of weedkillers, mechanical ( Pumps ,gearboxes,unloaders, engines petrol and diesel) repairs , seals, impregnators and there applications (including limitations of use ,application time frames,life expectancy ) , Various cleaning chemicals and there application and mix ratio's, affects of water on substrates in extreme conditions, absorption rates of different substrates, customers and difficult neighbours, stone repair, acid rain, symbiotic relationships between algaes and lichens, Pointing (synthetic and otherwise) Paint stripping,paint strippers ,Removal of sealers that have gone wrong /being wrongly applied. ...etc
So to ,answer you question .Yes... i have retained most of what i didn't fall asleep through.