Choose the right preposition in brackets according to the contents of the sentences (for, on, through, of). 1. why do detectives usually network of informants instead of meeting or interviewing people themselves? 2. the suspect can make a confession in plea bargain for a lesser sentence.

1. Why do detectives usually rely on a network of informants instead of meeting or interviewing people themselves?
2. The suspect can make a confession in exchange for plea bargain for a lesser sentence.