current
current is defined as the flow of positive charge. Specifically:
\begin{equation} I = \frac{\Delta Q}{\Delta t} \end{equation}
resistance of a wire (if ever you come across needing to calculate the resistance of the wire from scratch)
\begin{equation} R = \rho \frac{L}{A} \end{equation}
where, \rho is the material resistivity, L the length, and A the cross-sectional area.
you rarely need to do this!