Resposta:

a = 5m/s^2.

Explicação:

Vi = 0m/s.

Si = 0m.

V = ∆S/∆t.

a = ∆V/∆t.

a = (∆s/∆t - Vi)/∆t.

a = ( ∆s/∆t - 0 ) /∆t.

a = (∆s/∆t)/∆t.

a = ∆s/∆t^2

a = 180/6^2.

a = 180/36.

a = 5m/s^2.