Find an equation of a sphere if one of its diameters has endpoints (2, 4, 5) and (6, 8, 9).

Can some one me with these questions

Cody started biking to the park traveling 15 mph, after some time the bike got a flat so cody walked the rest of the way, traveling 4 mph. if the total trip to the park took 6 hours and it was 46 miles away, how long did cody travel at each speed? solve using rate times time= distance

The anwser cause i do not understand just plez