Q1) Name the type of biasing of a p-n junction diode so that the junction offers very high

resistance.Q2) Name the device which can represent digital data by analog signals and vice-versa.

Reverse bias offers very high resistance because depletion layer increases due to which  flow of majority charge carriers is less.

Devices which converts analog signals into digital signals are called A/D converts.
and Devices which converts digital signals into analog signlas are called D/A converts.