18
Well, J-Q-K is a run in Cribbage (one point for each card in a run), so you would count the run three times with a different Queen each time, so that would be 9 for the triple run. Then, you get two points for each pair, and with three Queens, you have three pairs that you can count, so that is 6 for the pairs. You don't have any combinations that make up 15, so your total is 15. I'm assuming that you are counting points for the Jack (if any) separately, as well as any Go during the play.
Depends on what game you're playing. Usually 1 or 11. (In some games, for example Blackjack, it's both 1 and 11)
ace
29
There are three spades on the standard ace of spades. One in each corner and a large one in the middle.
An ace is a number card. It is the number one. The one is called an ace, a two is a deuce, a three is a trey. In some card games an ace is a simple one card, just like a six or nine and is often called a 'one'. In games where the ace ranks higher than a king, it is always referred to as an 'ace'.
Blackjack, that is an Ace with any 10 value card.
One can find information about playing cribbage online at websites such as Pogo, Games and Candystand. If specific information is required then check Wikipedia.
This isn't an idiom because it's just one word that's confusing. The word "ace" in this sense is slang. It means to score highly or make a top grade.
that you can score three points in one shot
That's only one out of three.
If three aces have already been dealt with, there is only one ace left and 49 cards left. P(4th ace)=1/49 The odds are 1 to 49. It is here assumed that four cards cards are delat one by one and the first three were aces.