which in is it speed (s) or velocity (v)?
a bike goes 25 m/s toward
main street,
a person walks 4 mph.
a plane flies 200 m/s.
a bird flies 100 mph due
south,

Explanation:

Speed has only magnitude.

Velocity has magnitude and direction.

"A bike goes 25 m/s toward  main street."

This includes a direction, so it is velocity (V).

"A person walks 4 mph."

This has only magnitude, so it is speed (S).

"A plane flies 200 m/s."

This has only magnitude, so it is speed (S).

"A bird flies 100 mph due south."

This includes a direction, so it is velocity (V).

dang that balls went far