Which of the following is the correct mathematical definition for speed? LaTeX: \overrightarrow{v} = \frac{\Delta t}{\overrightarrow{d}} LaTeX: v = \frac{\overrightarrow{d}}{\Delta t} LaTeX: v = \frac{d}{\Delta t} LaTeX: \overrightarrow{v} = \frac{\overrightarrow{d}}{\Delta t}