18. [0/1 Points] DETAILS PREVIOUS ANSWERS EWENMATH12 6.6.001. 1/100 Submissions Used MY NOTES ASK YOUR TEACHER A set of seven built-in bookshelves is to be constructed in a room. The floor-to-ceiling clearance is 7 ft 3 in. Each shelf is 1 in. thick. An equal space is to be left between the shelves, the top shelf and the ceiling, and the bottom shelf and the floor. How many inches should there be between each shelf and the next? (There is no shelf against the ceiling and no shelf on the floor.) in