Respuesta :

Answer:

80 m/s

Explanation:

Given:

i) initial velocity (as starts from rest) = 0 m/s

ii) acceleration:  4 m/s²

iii) distance travelled: 800 m

Formula required:

(final velocity)² - (initial velocity)² = 2 × acceleration × distance

Now solve:

v² - 0² = 2 × 4 × 800

v² = 6400

v = √6400

v = 80 m/s