3. Consider the following state of a system with four processes, A, B, C, and D, and five types of resources, R1, R2, R3, R4, and R5. Current state is presented as follows (The first row is for A and the last one is for D). < C=10100 R=10211) E-(32451) A=(11320) 00010 31121 01010 10320 (10011) 12120 The corresponding safe sequence is: < (List the processes in form like "ABCD", DO NOT add any extra characters.)