Answer:
A Shunt is a passive element, usually resistive, that is used to bypass current around another element, like a meter, that is not able to handle the full current flow. ... A Multiplier is an active element that amplifies a voltage or current to enable a less sensitive device or circuit to make use of it.
Using the mirror formula.
1/v + 1/u = 1/f
1/9.5 + 1/3.2 = 1/f
1/f = 3.2 + 9.5 / 9.5 * 3.2
1/f = 4.82 cm
Radius = 2f
Radius = 2 x 4.82
Radius = 9.64 cm
Cesium has the least ionization energy and can donate electrons very easily !