Solution
 Life and death Problems and Huis Ten Bosch.

Problem 1. D1,C1,C2,B2,E1

Problem 2. R1,O1,N3,M1,M2

Problem 3. You can capture both groups of white by ori (Q1,N1,P1,S4 T3,T2,T4,T5,S5,S3,T4R1,S1,T3,T2,T4,T5,S5,S3,T4).

Problem 4.   S1,Q1,O1,T1,T2,T3,T1,R1,T1

Problem 5. T10 is a vital point (T10,A10,...).