Following steps are used to prepare a magnetic compass by using an iron needle and a bar magnet:
(i) Take a small piece of cork, and the magnetised needle (which can be magnetised by using a bar magnet).
(ii) Take a cup filled with water and let the cork float on it; the needle should not touch the water.
(iii) Now, compass is ready to work. Note the direction in which the needle points when the cork is floating.
(iv) Rotate the cork in different directions. Note the direction in which the needle points when the cork begins to float again without rotating. We see that the needle always points in the same direction, when the cork floats without rotation

Activity showing magnetic compass by using iron needle and a bar magnet

It can be found in following ways:
(i) Take the bar magnet with known poles in you hand.
(ii) Take one of the other two iron bars in other hand.
(iii) Bring one side of iron bar towards the south pole of the bar magnet and note down whether it is attracted or repelled.
(iv) Bring other side of iron bar towards the south pole of the bar magnet and again note down the same thing.
(v) If there is an attraction in both cases i.e.,(iii) and (iv), then it is definitely a simple iron bar.
(vi) If there is an attraction in one case and repulsion in other case, then it is a bar magnet.
(vii) Do the same for the third iron bar. Now, poles can be found in following ways-If in case (iii), the bar is attracted, then it is North pole of the identified bar magnet. If the bar is repelled, then it is a south pole of the identified bar magnet.

(i) Magnets can lose their magnetic properties if :
(a) exposed to heat.
(b) they are dropped or hanged on enough to bump their domains out of alignment.
(c) They are burnt up to their curie point (the temperature at which they get demagnetized completely.)
(ii) Safety measures to follows while storing horseshoe magnets :
(a) Always wear safety goggles when haning large magnets.
(b) Always wear gloves when handling magnets to prevent pinching.
(c) Children should NEVER be allowed to play with NEODYMIUM magnets
(d) Keep magnets at least 20 em away from sensitive electronic and storage devices.
(iii) When the magnet is suspended freely with the thread, it aligns itself in the geographic north-south direction. We use this property of magnet in compass to give us the directions at a particular place.
The diagram of the compass is shown in the figure below:

The poles of the bar magnet are located at its two end points. Place a magnet on paper and sprinkle some iron filings on it. It is observed that the iron filings get attracted more strongly towards the two ends of the magnet as compared to its central portion indicating that the poles are located at these two ends of the magnet

Yes, two pieces will work as an individual magnet because a monopole (single pole) of magnet never exists

As given in figures, the North pole will be far apart when we bring more near to the compass needle and it will be closer to it when we bring the South pole towards it.

The two ways to identify the magnet are
(i) Hang the metal bars with a thread and having its level horizontal one by one and let it stop in any direction. Now, if we move it by"pushing it slowly and it returns to the same direction, it means that it is a magnet otherwise it is an iron bar simply.
(ii) Take some iron filings and move the iron bars over these iron filings one by one. If iron filings are attracted very strongly at poles, then it is a magnet and if it is not attracted, then it is simply an iron bar.

Steps involved in the magnetising of an iron strip are
(i) Take an iron strip which is to be magnetised.
(ii) Keep it in a wooden table.
(iii) Hold one end of bar magnet in your hand and keep the other end of bar magnet at one end of iron bar.
(iv) Without lifting, move the lower end of bar magnet to the end of iron bar.
(v) After reaching end of iron bar, lift the bar magnet and bring it to the same position and repeat the process again and again.

To find out the magnet
(i) Take the bar magnet A in your hand.
(ii) Take the bar magnet B in other hand.
(iii) Bring one side of B towards South pole and note down it is attracted or repelled.
(iv) Bring other side of B towards South pole and again note down the same thing.
(v) If there is an attraction in both cases (iii) and (iv), then it is definitely an iron bar.
(vi) If there is an attraction in one case and repulsion in other case, then it is a bar magnet.
(vii) Do the same for the iron bar C.
To find out the poles:
If in case (iii) the bar is attracted, then it is North pole of the identified bar magnet. If bar is repelled, then it is obviously a south pole of the identified bar magnet.