Questions

During convection, cool and dense air falls through the warmer and less dense air. The warm air having less mass is being displaced by the cooler which is much heavy. Convection always involves the air rising through the atmosphere.

Internet service providers (ISP's) emerged in the late 1980's and early 1990's.

The ARPANET was decommissioned in 1990.

By 1995, the Internet was fully commercialized in the U.S., when the NSFNet was decommissioned, removing the last restrictions on use of the Internet to carry commercial traffic.

Bangalore-based Sagar Baheti has become the first visually impaired Indian runner to complete the historic Boston Marathon, the world's oldest and the hardest marathon to qualify for.

Hydroelectricity is electricity produced from hydropower i.e, water.

Two times IPL champions Mumbai Indians (MI) reached a new milestone as they became the first team in history to win 100 T20 matches. The Mumbai outfit defeated Kolkata Knight Riders (KKR) at the Eden Gardens by 9 runs in their final match of the league stage of IPL 2017.

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

Process Dispatcher,Vhand,Dbflush are the children of Scheduler