$3.$ Write a regular expression that generates exactly the set of valid $3-$consonant English onsets described above. $($e$.$g$.$ it should generate the strings $$S CH R$,$S K W$,$ etc. but not the strings $$S CH L$,$S P W$,$ etc.$)$ The language it generates will have a cardinality of $8.$ Hint: Since this is a finite language, you could in principle write this regular expression by writing out every valid onset individually. But this would be inefficient $($and would miss the point$)!$ Instead, find a way of writing it that takes advantage of the fact that some groups of segments behave similarly to each other.