7、The volunteer service team delivers newspapers to elderly people with mobility issues in the community. Xiao Ma is responsible for an elderly person living on the 7th floor. It takes 14 seconds to go up or down one floor, so it takes Xiao Ma a total of $\qquad$ seconds for a round trip up and down.
【Answer】168
【Analysis】From the first floor to the seventh floor, there are six intervals. It takes 28 seconds to go up or down one floor, so the total time for going up or down the stairs is $(7-1) \times 28=168$ seconds.