Hint: Firstly we have to conclude that both the instruments belong to the communication industry and have a specific functionality regarding the transmission process of the waves that travels. The transducer is basically the energy converter whereas the repeater is the device that basically takes the wave and transmits it into the channel.
Complete step by step answer: a.Transducer: i. A transducer is a device which converts one form of energy into another one. ii. Generally a transducer is responsible for converting signals in one form of energy to signals in another. iii. Transducers are often employed at the boundaries of automation, measurement, and control systems. iv. Microphones, speakers are general day to day examples as they convert electrical signals to sound and vice versa. b. Repeaters: i. Repeaters are the devices that get an electronic signal and then re-transmits it to some channel. ii. Repeaters are used to extend transmissions so that the signal can cover longer distances or be received on the other side of an obstruction. iii. Some types of repeaters broadcast an identical signal, but they usually alter the method by they are transmitted to increase the efficiency. For example, on another frequency or a braud rate.
Note: These are communications and transmission equipment and should be handled with care. Apart from that they are generally in every day to day equipment so we may can,t notice them working but can find how and where they are working.