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Over the past decade, brands that were once available only to the wealthy have created more affordable product extensions, giving a far broader range of consumers a taste of the good life. jaguar, for instance, launched its x-type sedan, which starts at $30,000 and is meant for the "almost rich" consumer who aspires to live in luxury. by marketing to people who desire a luxurious lifestyle, jaguar is using:

Alarge tank is filled to capacity with 500 gallons of pure water. brine containing 2 pounds of salt per gallon is pumped into the tank at a rate of 5 gal/min. the well-mixed solution is pumped out at the same rate. find the number a(t) of pounds of salt in the tank at time t.

From what part of income should someone take savings?