Problems $(7$ pts$/$each$,$ except the last one which is $5$ points$)$

$4\mathrm{.}1$ It was pointed out that two advantages of using multiple threads within a process are that $(1)$ less work is involved in creating a new thread within an existing process than in creating a new process, and $(2)$ communication among threads within the same process is simplified. Is it also the case that a mode switch between two threads within the same process involves less work Ithan a mode switch between two threads in different processes? Explain your answer.