Answer:
t = 1.9 s
Explanation:
    [tex]a = \frac{v_{f} -v_{o} }{t_{f} - t_{o} } (1)[/tex]
    [tex]v_{f} = v_{o} + a*t (2)[/tex]
    [tex]t =\frac{v_{f}-v_{o}}{a} (3)[/tex]
    vf = 6.3 m/s
    v₀ = 1.2 m/s
    a = 2.75 m/s²
    [tex]t =\frac{v_{f}-v_{o}}{a} = t =\frac{6.3m/s-1.2m/s}{2.75m/s2} = 1.9 s (4)[/tex]