Exams

Sad means being unhappy, sorrowful, mournful, wistful,...

Hence, Somber means cheerless i.e, unhappy which is synonym of sad. All other options are opposites of Sad.

An Ice Cube is what made of water and will die if we put it in water.

Gum.

Most of the emissions of greenhouse gases (GHG) come primarily from burning fossil fuels (coal, hydrocarbon gas liquids, natural gas, and petroleum) for energy use and the major greenhouse gas is of course carbon dioxide (CO2) which comes from burning fossil fuels and land-use change.

But methane (CH4) and nitrous oxide (N2O), which mostly come from agriculture and waste, are also significant GHGs and shouldn't be discounted.

Hubs are specified or operate at Layer1 i.e, the physical layer in the OSI model. Hubs regenerate electrical signals. A hub sends data packets (frames) to all devices on a network, regardless of any MAC addresses contained in the data packet.

In computers, generally Font size is measured in points (pt).