Which of the following can you do with a variable that has been declared using let? $($select all that apply$)$

Group of answer choices

If the variable$$s value is a number, increase its value by $5$

If the variable$$s value is the string $$Hello$,$ add $$ World$$ to the end

I don't know

If the variable$$s value is an array, add an element to the end

None of these answers