Difference between priority inheritance and priority ceiling protocol?

Answer 1

priority inheritance: when a job blocks one or more high priority jobs, it ignores its original priority assignment and executes its critical section at the highest priority level of all the jobs it blocks.

priority ceiling: gives each shared resource a predefined priority ceiling. When a task acquires a shared resource, the task is hoisted (has its priority temporarily raised) to the priority ceiling of that resource. It will not see whether the job has been blocked or not, simply it raises to the priority of the shared resource.