Step 1: An ammeter is designed to measure larger currents with lower resistance, whereas a milli-ammeter measures smaller currents and therefore requires higher sensitivity.
Step 2: Since a milli-ammeter is more sensitive, it has higher internal resistance compared to an ammeter. \[ \therefore x_1<x_2 \] \[ \boxed{x_1<x_2} \]

What is the first law of Kirchhoff of the electrical circuit? Find out the potential difference between the ends of 2 \(\Omega\) resistor with the help of Kirchhoff's law. See the figure: