score:3
When a sentence in the Old Testament ends with a question-mark, it needs to be borne in mind that the writer, in and of himself, might not have yet know the answer. He's writing a thought that troubled him. You have listed five such questions. Of course, some questions are rhetorical, such as God's list of questions to Job (chapters 38 to 42, which silenced Job and had him repenting in dust and ashes, vs. 6). A great example of what I mean is the writer of Ecclesiastes asking if, at death, the spirit of animals is any different to the spirit in man - does one go down and the other go up? (3:21) Yet by the end of his book he has got the answer to what happens to the spirit of man at physical death - it goes up to God and the person will have to account to God! (12:7)
I'm answering as one who believes that dead physical bodies rot in the grave, unconscious and totally unaware, but that the spirits of dead humans arise to return to God, for judgment (as that chapter in Ecclesiastes shows.)
So, how do I explain those Psalms you have selected? I have already flagged up the need to check whether those that are questions are stating a fact (rhetorically) or if the asker just does not know himself, at that stage. Then I would collate all the other Psalms that provide more information with which to arrive at a conclusion. For example:
Psalm 49:7-15: Speaks of the futility of humans hoping to redeem their bodies from the corruption of the grave, then adds - "Like sheep they are laid in the grave; death shall feed on them [etc] But God will redeem my soul from the power of the grave: for he shall receive me." Said before knowing of Christ as Redeemer.
Psalm 73:24-26: Speaks of foolishly envying the wicked, then adds - "Nevertheless I am continually with thee: thou hast holden me by my right hand. Thou shalt guide me with thy counsel, and afterward receive me to glory. Whom have I in heaven but thee? There is none upon the earth that I desire beside thee. My flesh and my heart fail, but God is the strength of my heart, and my portion for ever." Said before knowing of Christ as Redeemer.
Psalm 90:9-10: Speaks of human life being generally restricted to 70 or 80 years, then adds - "Yet is their strength labour and sorrow; for it is soon cut off [in death] and we fly away." Said before knowing of Christ going to prepare a place in heaven for his people.
Psalm 116:15: Speaks of the need to pay one's vows to God, for, "Precious in the sight of the Lord is the death of his saints." Put that together with Psalm 72:14.
Those are just a few. Don't forget that other writers, in other places of the Old Testament, also spoke of living after death. And don't forget that those who insist there is no awareness of any invisible part of a dead person will always interpret those Psalms as speaking of oblivion in the grave until God re-creates them in the resurrection. Well, they would, wouldn't they?