following changes can be made safely $($without introducing the possibility of deadlock$),$ and under what circumstances? a$.$ Increase Available $($new resources added$).$ b$.$ Decrease Available $($resource permanently removed from system$).$ c$.$ Increase Max for one thread $($the thread needs or wants more resources than allowed$).$ d$.$ Decrease Max for one thread $($the thread decides it does not need that many resources$).$ e$.$ Increase the number of threads. f$.$ Decrease the number of threads.