Explicação:

1) Alternativa C

2)

[tex]a = \frac{Δv}{t} [/tex]

[tex]a = \frac{18 - 8}{4} [/tex]

[tex]a = \frac{10}{4} = 2.5 \: \frac{m}{ {s}^{2} } [/tex]

3)

[tex]ΔS = vo \times t[/tex]

[tex]400 = 200 \times t[/tex]

[tex]t = 2 \: horas[/tex]

4)

[tex]36 \: \frac{km}{h} = 10 \: \frac{m}{s} [/tex]

[tex]ΔS = vo \times t[/tex]

[tex]ΔS = 10 \times 2[/tex]

[tex]ΔS = 20 \: metros[/tex]

[tex]vm = \frac{ΔS}{t} [/tex]

[tex]vm = \frac{20}{2} [/tex]

[tex]vm = 10 \: \frac{m}{s} [/tex]