Find (f ° g)(x) and (g ° f)(x) f(x) = 7x-4, g(x)=5-3x

The table above shows approximate conversions from gallons to liters. what is the value of x?

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The water company charges a residential customer $41 for the first 3,000 gallons of water used and $1 for every 200 gallons used over 3000 gallons. if the water bill was $58 how many gallons of water were usedanswersa 3400 gallonsb 6000 gallonsc 6400 gallons d 7000 gallons