Questions

Yaounde is the capital of Cameroon

August Weismann cut off the tails of mice for 21 successive generations and still they produced generation after generation of only tailed young ones. So he concluded that acquired characters are not inherited.

southern region is closest to equator and thus receives sunlight for longer duration than any other part of India

Cryogenic Engines find applications in Rocket technology. A cryogenic rocket engine is a rocket engine that uses a cryogenic fuel or oxidizer, that is, its fuel or oxidizer are gases liquefied and stored at very low temperatures. Notably, these engines were one of the main factors of NASA's success in reaching the Moon by the Saturn V rocket.

Sodium hydroxide - NaOH is caustic soda

Sodium carbonate - Na2CO3 is washing soda

Sodium bicarbonate - NaHCO3  is baking soda 

12 N in a C means 12 Numbers in a Clock.