Hello i have last 10 min can u answer these questions please ?

Which of the following memory allocation schemes can cause external fragmentation? a. Multiple contiguous fixed partitions of equal size b. Paging c. Segmentation d. Sweeping e. Multiple contiguous fixed partitions of various sizes Q2 Operation V on a raised binary semaphore: Select one or more: a. It does not change the value of the semaphore b. It is stored in order to be able to perform as many operations P as there were V c. Increases semaphore value by 1 Q3 The operating system plays the following role in a computer system: Select one or more: a. creating abstraction (virtualization) of hardware b. Create a concurrent environment c. relational database management d. computer system resource management Q4 The operating system plays the following role in a computer system: Select one or more: a. creating abstraction (virtualization) of hardware b. Create a concurrent environment c. relational database management d. computer system resource management