Questions

The water rise in a capillary tube dipped in water is such that the weight of water in the tube above the surface of water in the vessel is equal to (balances) the upward force due to surface tension. So it is clear that if the the bore (radius) to the tube is decreased, the height of the water column in it must be greater.  So, (a) is correct.

Normal Gas welding use oxygen-acetylene.

Depending on what materials you are welding, there are some more options that might be used.

For example - MIG/TIG use Argon, MAG use an argon-something mix.

Ethylene is used for Artificial Ripening of Green Fruit.

• Calcium carbide is also used in some countries for artificially ripening fruit. When calcium carbide comes in contact with moisture, it produces acetylene gas, which is quite similar in its effects to the natural ripening agent, ethylene

The letter “c” with a line over it is a medical abbreviation often used by doctors, nurses, and other medical professionals. The symbol looks like this: c̄. The c is almost always lower-case.

This symbol actually has a very simple meaning. A c with a line over it just means “with”. This abbreviation is often used on patient charts and prescriptions, as well as information or notes written by medical professionals.

The Room can Nobody Enter is a Mushroom.