Questions

Let speed of train B be x m/s And length of train B be y m
Then length of train A is 2y m
Speed of train A = 84 × 5/18 = 210/9 m/s = 70/3 m/s
A.T.Q, (2y+y)/10 = 70/3 − x .............(i)
and (2y+y)/ 22.5 = 70/3 − 2x ................(ii)
solving (i) and (ii), y = 50 m

The letter 'X' resembles the same as the tool AXE in sounding.

Hence, the alphabet X is a tool.

India has acquired the top position among 30 developing countries on ease of doing business at the 2017 A.T. Kearney Global Retail Development Index (GRDI). The 2017 GRDI titled “The Age of Focus” ranked China at second place, followed by Malaysia, Turkey, United Arab Emirates (UAE) and Vietnam. The 16th edition of GRDI ranked top 30 developing countries for retail investment worldwide and analyzed 25 macroeconomic and retail-specific variables to help retailers devise successful global strategies to identify emerging market investment opportunities.

Stratification as actually the settling down of sediments with different properties to form layers/strata over years. Stratification especially occurs on the bed of water bodies such as oceans.

Stratified sedimentary rocks are used to study the ecological conditions over previous years/eras.  

The other choices like Windstorms, Glacial Ice and Stream water are mediums which sediments are transported.

A clipboard is a temporary storage area for items that the user wants to cut or copy from one place to another.

For example, in a word processor application, the user might want to cut text from one part of a document and paste it in another part of the document or somewhere else, it is temporarily stored in clipboard.