Please answer the 4 multiple choice questions below:

A thread that gains possession of a spin lock will cause all other threads on the system to immediately enter the block state. True False A thread of a user process can execute only in its own process address space or the kernel address space. True False If the page replacement algorithm being run by the page-purges thread selects a modified page (dirty page) from a memory object for replacement, that selected frame can be placed immediately on the free list. True False If using a linked-list allocator, when a dynamically allocated memory chunk is returned (made free again), we need to place it back into the linked list. To do this we must: always build a new header for the free block and insert it into the existing free list coalesce the free block only with adjacent shallow address free blocks always coalesce with any adjacent free block(s) and only build a new header if required coalesce the free block only with adjacent deep address free blocks