Questions

A karst topography is that which composes of limestone and its associated features and structures. Karst topography and caves develop in limestone rocks due to their solubility in dilute acidic groundwater. The solubility of limestone in water and weak acid solutions leads to karst landscapes.

Flowing rivers, can be found in areas away from karst topography.

The logical answer for a puzzle is that the letter 'W'.

A rainbow is a spectrum of light that appears in the sky when sunlight is refracted through raindrops or other drops of moisture in the Earth's atmosphere. They have inspired much popular folklore, including the belief that a leprechaun can be found with a pot of gold at the end of a rainbow.

The World Environment Day (WED) is observed every year on June 5 to raise awareness about forests and wider issues of environmental protection. The 2017 theme is ‘Connecting People to Nature’. It implores us to get outdoors and into nature, to appreciate its beauty and to take forward the call to protect the Earth that we share. The host country for the WED 2017 is Canada, where the official celebrations take place.