WORTH LOTS OF POINTS

Consider the function y = f(x)=3^x the values of f(1/2) and f(1/4). rounded to the nearest hundredth, are__and__ respectively

Mr. vector door is buying two new cowboy hats all together the hats cost $75.12 the second heart cost twice as much as the first hat what is the price of the more expensive at round to the nearest hundredth

X/y + 4y/x divided by x/y - 2y/x explain as in depth as you can how you simplfied the fractions. i don't know where to start on this : /