Yes, including the good ones, which is where most businesses stop bothering. Replies are public, free, and one of the very few things about a listing that is entirely within your control.
Connect Google first
We cannot see which reviews have gone unanswered until you connect your Google Business Profile. Until then this is left out of your score rather than counted against you. It is a fact we are not allowed to look at, not one we are guessing at.
What to write
Two sentences is plenty. Thank them, and name the job. "Glad the ceramic coating came out well" tells a machine what you do as well as thanking a customer, which is a second reason to be specific.
Reply to the bad ones too, calmly and without relitigating. The reply is not really for the reviewer. It is for the next person reading, and for whatever is summarising what people say about you, and a measured reply under a one-star review persuades more readers than the review does.
Then keep up with them
Once you are level, new reviews take a minute each. This is one of the few signals on the whole list that costs nothing but attention.