What is the direction of electric current inside an electrolyte?

The electric current flowing through a given conductor varies with time as shown in the graph below. The number of free electrons which flow through a given cross-section of the conductor in the time interval $0 \leq t \leq 20 \ s$ is

$A$ current of $5\,A$ flows through a resistance of $10\, \Omega$ for $4$ minutes. The total charge in Coulombs and the number of electrons passing through any cross-section of the resistor in this time are, respectively:

In a hydrogen discharge tube,it is observed that through a given cross-section,$3.13 \times 10^{15}$ electrons are moving from right to left and $3.12 \times 10^{15}$ protons are moving from left to right per second. What is the electric current in the discharge tube and what is its direction?

Define electric current and explain it. Write its $SI$ unit.

An electron (charge $= 1.6 \times 10^{-19} \text{ C}$) is moving in a circle of radius $5.1 \times 10^{-11} \text{ m}$ at a frequency of $6.8 \times 10^{15} \text{ rev/s}$. The equivalent current is approximately: