A divider, measured

// A divider, and a meter on it.
//
// Three 10 k resistors from 5 V down to ground. No current goes anywhere else,
// so the same current is in all three and each one drops the same third of the
// supply:
//
//   I = 5 V / 30 k = 167 uA
//   each resistor  = 167 uA x 10 k = 1.667 V
//
// The meter's red lead is on the lower tap, which is one resistor above
// ground, so it reads 1.667 V. Move it to the middle tap (the strip at column
// 14) and it reads 3.333 V, which is two thirds of the supply.
//
// The other three positions on the dial, all on this one circuit:
//
//   A=   break the chain and put the meter in series (red lead to the A jack,
//        which is the one that carries current) and it reads 167 uA. The
//        meter's shunt is 1 ohm, so it costs the circuit 167 microvolts to
//        measure it.
//   O    stop the simulation, take the 5 V supply off, and the ohms range
//        reads 10 k across one resistor and 20 k across two. Ohms pushes its
//        own small test current, so it only means anything with the power off.
//   .)   continuity. Across a resistor, nothing; across a plain wire, the lamp
//        lights, which is how you find the break in a circuit that should work.
//
// The meter loads what it measures, exactly as a real one does: 10 Mohm across
// the lower tap next to a 6.7 k source pulls it down by 6.7 k / 10.0067 Mohm,
// which is seven hundredths of a percent, and that is why it reads 1.666
// rather than the 1.667 the arithmetic above gives.