These three stocks benefit from megatrends that will drive earnings growth for many years.Heating, ventilation, and air conditioning (HVAC) company Carrier Global (CARR -0.24%), building materials company Owens Corning (OC 1.08%), and copper miner Freeport-McMoRan (FCX 0.58%) have all received Wall Street analyst upgrades recently, and justifiably so. These three stocks present a promising opportunity for investors to capitalize on positive trends, potentially leading to significant profit. Here's why.1. Ca ...