Which of the following are true regarding Javascript code? $($select only correct answers$)$

If "phrase$1"$ and "phrase$2"$ are both string variables, you can concatenate them with this code $-$ phrase$1+$ phrase$2$

If "phrase$1"$ and "phrase$2"$ are both string variables, you can concatenate them with this code $-$ "phrase$1"+$ "phrase$2"$

If the variable named "sentence" is a string, this code will output its value to the screen $-$ document.write$("$sentence$")$;

If the variable named "sentence" is a string, this code will output its value to the screen $-$ document.write$($sentence$)$;