Interrupts in the ARM v7-M are handled by the Nested Vectored Interrupt Controller (NVIC). The NVIC has two functions, to enable interrupts and to assign priority to interrupts. Up to how many interrupt sources can the NVIC support? How can the software determine how many external interrupt lines are supported by an implementation? Where does the interrupt vector table reside in the memory layout of a Cortex-M4 microcontroller? How can the priority of interrupts be changed? How can the software support multiple interrupt vector tables