Classic duplicate hand.

North should not open with these poor 10HCPs, balanced and no Aces.

Easts 9HCPs shape and Aces is nearer to opening.

South will open 1♥ .

East then could bid 2♥ s Michaels cue bid showing 5+/5+ in ♠ s and a minor.

North could try 3♣ being not vulnerable showing no support for ♥ s and close to opening points.

Over a pass East would bid 2N to ask for Wests minor suit.

Over 3♣ by North, East could assume that Wests suit is ♦ and risk 3♦ 

Over 3♦ South may be tempted to show his 5 card ♥ suit.

So many final contracts.

N/S 3♣ or 3♥ 

E/W 3♦ 

Whoever declares will score well.

How to bid preempts and how to do deal with them. 

If you can preempt they make life difficult for the opposition. If in doubt whether to preempt - do it.

South has to decide what to do? 4♣ or perhaps 3♣ due to the vulnerability. The rule of 2,3,4 could apply here. The K♠ singleton is not useful. The rule of 2 would suggest 3♣.

West will be tempted to make a double, but he is not strong enough.

North does not have enough ♣ support and has defensive values so may try and make it difficult A9♣ would be useful in offense and make it difficult for East to bid.

What to do in responding, Andrew Robson introduces the concept of useful points UP where you discount Q and Js, so here North has just 10 UPs (12 HCPs) So here North would pass 3♣.  

So many will pass with North. 

East has a perfect shape to double but poor HCPS Kaplan Hand Evaluator shows 9.75HCPs (Q singleton not useful) but he is in the balancing seat. 

Risky but if he doubles E/W are likely to find the making 4♠ contract. Otherwise 3♣ will make.

Winning the last trick with the 7♦  (When ♦ are not trumps) is the beer or nowday tge drinking card. Here is a bit of history and various rule variants of the beer card on Wikipedia.

This was the hand with an interesting duplicate hand as well as trying to win with the 7♦ 

West will pass and North will bid 1♣ East will pass and South will bid 1♠ (2♠ is normally played as weak preemptive - but some people play it as strong, so make sure you are clear with your partners) 

North will start showing  shape by bidding 2♣ 

South would like to bid 3♠ to show shape, but this is not forcing, So will start with Fourth suit Forcing. Andrw Robson on Fourth suit forcing. https://www.andrewrobson.co.uk/article/articles/394 ANDREW’S TIP: When the first three bids between a partnership are in different suits, a bid of the fourth suit shows a game going hand and asks partner to describe his hand further.

Do south bids 2♥ .

The choices for North are to give support for partner if he has it or bid NTs if he has a stopper in the FSF or bid out his hand further. No need to rush so North will probably bid 2NT. South can rebid ♠ s probably showing 6.

North then has a difficult decision whether to bid 4♠ or to bid 3NT, in duplicate 3NT is probably best.

After a fairly normal play of leading the K♥ (with bidding likely to be opponents shortest suit). North will hold up and take the Ace ♥ s on second trick in case the ♥ s are 5/2.

Declarer will run the ♠ s and throw the ♣ s.

Winning 7 tricks.

Ending with these cards

North ♦ A J 7 5 4

South to play with ♦ K 9 2 ♣ K 4

To make the contract play A and K ♦ 

If you play K♦ and then finesse the J♦  (a 50% choice due to the lead and lack of bidding) you risk losing and making only 8 tricks!

But this finess allows to win with the 7 ♦ beer card!!