Please answer this question

Briefly answer the following questions

a) Explain the relation of bootstrap program (sometimes called firmware) and kernel.

b) Why do some I/O devices have local buffers? How is this buffer used in the interaction between the I/O device and the CPU?

c) What is the condition for a process to be moved from ready queue to I/O queue? What is the condition for a process to be moved from I/O queue to ready queue?

d) Explain the critical section problem.