Concept:
Displacement from a velocity-time graph is equal to the area under the velocity-time graph.
Here, the velocity-time graph is a straight line from \(0\) to \(20\ \text{m/s}\), so the area is triangular.
Step 1: Identify base and height of the triangle.
Base of the triangle:
\(\displaystyle 10\ \text{s}\)
Height of the triangle:
\(\displaystyle 20\ \text{m/s}\)
Step 2: Use area of triangle.
\(\displaystyle \text{Displacement}=\frac{1}{2}\times \text{base}\times \text{height}\)
\(\displaystyle =\frac{1}{2}\times 10\times 20\)
\(\displaystyle =100\ \text{m}\)
Step 3: Final conclusion.
Hence, the displacement in \(10\ \text{s}\) is:
\(\displaystyle \boxed{100\ \text{m}}\)