A stone is projected straight upwards from point $X$ at time $t = 0$. The graph shows how the velocity $v$ of the stone changes with time $t$. What is the displacement of the stone from point $X$ at time $t = 3.0\,\text{s}$?
- A$15\,\text{m}$ above $X$
- B$15\,\text{m}$ below $X$
- C$25\,\text{m}$ above $X$
- D$25\,\text{m}$ below $X$