<p>A projectile fired at&nbsp;<span class="equation">\(30^0\)</span>&nbsp;to the ground is observed to be at same height at time 3s&nbsp; and 5s&nbsp; after projection, during its flight. The speed of&nbsp;projection of the projectile is_____<span class="equation">\(ms^{-1}\)</span></p>

<p>(Given g = 10&nbsp;<span class="equation">\(ms^{-2}\)</span>)​​​​​​​</p>