A distributor of flowable medium for a heat exchanger has a housing member and at least one substantially vertically oriented tube member arranged therein. Even if a radical initiator is not used, a monomer can be subjected to a radical polymerization to obtain a polymer having narrow molecular weight distribution. A current-amplifying, light-emitting transistor device including the current-amplifying transistor device and an organic EL device portion formed in the current-amplifying transistor device is also disclosed. A method detects insertion of a stylus into a charging unit having an internal battery and an interface capable of receiving power from an external power source.