Verified answer

α=30°    t=2 c    s=?

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s=t*vo*cosα=vo²*sin(2α)/g

sin(2α)=2*sinα*cosα

vo=g*t/(2*sinα)

s=g*t²/(2*tgα)=10*2²/(2*0.577)≈34.7 м

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