CNN  —  Prime members can now add “fuel discounts” to their ever-growing list of benefits. The newest perk from e-commerce giant Amazon will allow members to save 10 cents per gallon at the gas pump (up to an average of nearly $70 a year) at around 7,000 participating BP, Amoco, and AM/PM stations across the US. Members can avail themselves of the discount by linking their Amazon account to Earnify, a loyalty program app by BP. Data from GasBuddy shows that gas prices are at their lowest since