Blackjack table

Basic strategy says to split 7s against a dealer 2, and double after split is allowed, which makes splitting slightly better.

Hard 13 against a dealer 2 is a basic strategy stand, since the dealer busts often enough with a weak upcard and doubling or hitting has lower expected value.

Hard 17 against a dealer 2 is a clear stand; hitting risks busting and doubling would be far worse.

Hard 20 is a very strong hand against a dealer Ace; standing is the basic-strategy play, and splitting tens is worse in expectation.

Hard 15 against a dealer 10 is a basic strategy hit because no surrender is available, and doubling is clearly worse.

Hard 20 against a dealer Jack is a strong hand, so standing is clearly correct; hitting would almost certainly make it worse.

Hard 19 against a dealer 10 is a clear stand under basic strategy; hitting risks busting and doubling has negative expected value.

Hard 20 against a dealer 4 is a strong hand, and basic strategy says to stand. Splitting tens is a slightly worse play in a standard shoe.

Hard 10 against a dealer 5 is a strong doubling spot, since the dealer is likely to bust or finish weak and a 10-value card gives me 20.

Hard 20 against a dealer 8 is a strong hand, and standing is the basic strategy play. Splitting tens gives up a strong made hand for more risk.

Hard 19 against a dealer 5 is a clear stand; hitting or doubling has lower expected value.

Hard 14 against a dealer 10 is a basic strategy hit, since standing loses more often than hitting. Dealer has peeked and has no blackjack, but 14 is still too weak to stand on.

Hard 20 is a very strong hand against a dealer 10; hitting would almost certainly make it worse, so standing is correct.

Hard 17 against a dealer ten-value upcard is a stand in basic strategy; hitting risks busting too often and doubling is clearly worse.

Hard 5 against a dealer 8 is a basic strategy hit; doubling on such a low total is not favorable.

A hard 10 against a dealer 8 is far too weak to stand on, and doubling is not legal with three cards, so hitting is the best available play.

Hard 20 against a dealer 8 is a strong hand, so standing is clearly correct and hitting would almost certainly bust.

Hard 12 against a dealer 3 is a hit in basic strategy for 6 decks with the dealer standing on soft 17, so I hit.

Hard 18 against a dealer 3 is a clear stand; hitting risks busting and gives up a strong made hand.

Soft 18 against a dealer 6 is a standard double in basic strategy, including with S17 rules and 6 decks, since the dealer busts often and doubling gains value.

Hard 13 against a dealer 7 is a hit by basic strategy, since the dealer likely has a made hand of 17 or better and standing loses more often. Doubling is not favorable with a hard 13.

Hard 10 against a dealer 6 is a strong doubling spot, so doubling maximizes expected value.

Hard 13 against a dealer 6 is a standard stand, since the dealer busts often and doubling 13 is not favorable.

Hard 15 against a dealer Ace (who has already peeked and has no blackjack) is a weak hand; standing loses more often than hitting, and doubling is unfavorable, so basic strategy says hit.

Hard 19 against a dealer Ace is a clear stand; hitting risks busting with little chance of improvement. The dealer has already peeked for blackjack.

Hard 15 against a dealer 7 is a basic strategy hit, since standing loses more often than hitting in the long run and doubling is not favorable.