How the aiming feature works on angry birds

In this 'x(t) = x0 + v0 * t + 0.5g * t^2 ’ what do you mean by the time word? Will the bird collide with the obstacles at this time? Where should we place the pixels?

what do you mean by the time word? Do we expect the bullet or bird to collide with the obstacles at this time?
Where should we place the pixels?