Questions

A search engine is a information retrieval program that constantly collects information on the Web, following links in Web sites and reading Web pages. The search results are presented in a list format and are called as hits.

A metasearch engine is a search tool that uses another search engine's data to produce its own results from the Internet. These engines take input from a user and simultaneously send out queries to third party search engines for results. It searches other search engines rather than individual Web sites.

Examples of Metasearch engine includes - Dogpile, Zoo, Yabado, Metager, etc...

There are approximately 6 trillion miles in a light-year, so the distance we need to go is 6 trillion miles / light-year times. 4 light-years is equal to 24 trillion miles. So, this whole would take 1.2 billion hours. There are 24 hours a day and 365.25 days per year, so this time in years is 137 thousand years.

ECHO.

Photosynthesis is a process used by plants and other organisms to convert light energy into chemical energy that can later be released to fuel the organisms activities.

Photosynthesis can be represented using a chemical equation.

The overall balanced equation is

              $$\begin{gathered} 6CO2 + 6H2O →Sunlight C6H12O6 + 6O2 \\ Source of Carbon & Oxygen + \\ Source of Electrons & Hydrogen + \\ Energy that drives Photosynthesis ----> \\ Sugar + Gas produced by splitting water. \end{gathered}$$

Where 

CO2 = carbon dioxide 

H2O = water

C6H12O6 = glucose 

O2 = oxygen.

Oxygen is the final electron acceptor of cellular respiration.