At an amusement park there’s only enough room for 4,500 people to be in it at any time. the manager has also worked out that there needs to be 2,800 people in the park to make a profit after all the overhead costs and employee pay. if people are entering the park at a rate of 12 people a minute, and there are 850 people in the park currently, between how many minutes should the doors stay open to let guests in?