Speed after falling from rest for 2.0 s using g = 9.8 m/s^2

Assumptions: ignore air resistance, take downward as positive, and use g = 9.8 m/s^2.
Use v_f = v_i + gt.
v_f = 0 m/s + (9.8 m/s^2)(2.0 s)
v_f = 19.6 m/s downward
The speed is 19.6 m/s downward.