Which of the following is a true statement? The oceans replenish groundwater.
The oceans provide water for rivers and streams.
Lakes are only found in the Northern Hemisphere.
Coral reefs and sandbars create lagoons.

Coral reefs and sandbars create lagoons.

Explanation:

"The combination of coral growth and water creates a lagoon. It may take as long as 300,000 years for an atoll formation to occur. Coastal lagoons form along gently sloping coasts. They are generally shallower than atoll lagoons and tend to be separated from the ocean by an island, reef, or sand bank." I got my information from google :)

Hope this helps :

if the thermos has a vacuum innner, then heat through conv currents and conduction are reduced = vacuum flask

no. bullets are macro objects. wave nature is for light waves, extremely tiny particles. if a light particle was the size of your finger, the bullet would be the size of the universe. so basically, that huge difference in size makes the wave nature of matter insignificant.