Respuesta :

Answer:

b) 18 m/s is the correct answer.

Explanation:

initial velocity(u) = 30m/s

acceleration(a) = -4m/s²

time(t) = 3 seconds

final velocity(v) = ?

using the formula,

a = (v-u)/t

or, -4 = (v-30)/3

or, -12 = v-30

or, v = -12+30

so, v = 18 m/s