$($a$)$Galaxy A is reported to be receding from us witha speed of $0\mathrm{.}35$c$.$ Galaxy B$,$ located in precisely theopposite direction, is also found to be receding fromus at this same speed. What multiple of c gives therecessional speed an observer on Galaxy A would findfor $($a$)$ our galaxy and $($b$)$ Galaxy B$?$