Relation of giant thermo-emf, magnetothermo-emf, magnetoresistance, and magnetization to magnetic impurity states in manganites Nd$_{(1-x)}$Sr$_{x}$MnO$_{3}$ и Sm$_{(1-x)}$Sr$_{x}$MnO$_{3}$

Thermo-EMF, magnetothermo-EMF, magnetoresistance, and magnetization of single-crystal samples of Nd$_{(1-x)}$Sr$_{x}$MnO$_{3}$ и Sm$_{(1-x)}$Sr$_{x}$MnO$_{3}$ with 0 $\le x\le$ 0.3 have been studied experimentally. A sharp increase in the thermo-EMF and giant magnetothermo-EMF and magnetoresistance has been observed near the Curie point $T_C$ in compounds with 0.15 $\le x\le$ 0.3. At the same time, no peculiarities have been found in compositions with $x$ = 0. Since compounds with $x>$ 0 consist of ferromagnetic clusters of the ferron type that reside in an antiferromagnetic $A$-type matrix, this means that the sharp increase in the thermo-EMF near $T_C$ is caused by ferrons. Indeed, the disappearance of ferrons due to a magnetic field or heating above $T_C$ leads to an abrupt decrease in the thermo-EMF. Therefore, thermo-EMF in alloyed magnetic semiconductors has been determined by the impurity concentration and the sample volume.