A robot fires a tennis ball to protect itself from an incoming baseball. The trajectory of the tennis ball shot from the robot is given by r(s)=⟨10−20s,103–√−203–√s,15s−5s2⟩, where r(0) is the position of the robot, and the baseball has a trajectory given by b(t)=⟨5t,53–√t,10t−5t2⟩, t≥0. At what time t0 should the robot fire the tennis ball so that it collides with the baseball?