<image>To respond to the public event "Low Carbon and Green Travel," Xiao Yan and her mother decide to ride bicycles to the library on Sunday to borrow books. They start from home at the same time. Xiao Yan first rides at a speed of 150 meters per minute for some time, rests for 5 minutes, and then rides at a speed of m meters per minute to the library. Her mother rides at a constant speed of 120 meters per minute. The relationship between the distance y (meters) and the time x (minutes) for both is shown in the diagram. Based on the graph, answer the following questions:
(1) The distance from Xiao Yan's home to the library is ______ meters;
(2) a = ______, b = ______, m = ______;
(3) The function expression for the distance y (meters) that the mother rides concerning time x (minutes) is ______; the domain is ______.