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(d) Over what time interval will the concentration of salt in the water be less than 4%? Use algebraic methods to determine the answer.8. (12 points) Some Guy's Mixing Solutions is a company created and owned by the infamous Some Guy. One of his biggest clients is the local sea aquarium, which requires Some Guy's company to mix large quantities of specific brine (salt water solution). One day, in the aquarium's largest tank to house some new hammerhead sharks, the company determines that to fill the aquarium with the appropriate brine solution, they must first mix in 50 kg of salt with 1000 gallons of pure water. Then, for every 1 hour after the initial mixture, the company adds in another 10 kg of salt and another 300 gallons of water. (a) Determine a function B(t) which gives the concentration of salt in the water, B (in kg of salt per gal of water), after t hours. (b) After how many hours is the concentration of salt in the water 4.5% (4.5 kg salts per 100 gallons of water)? Use algebraic methods to determine the answer. (c) What concentration will the brine solution eventually reach if this process were to go on indefinitely? Explain