Questions

MS Excel is the widely used worksheet in computer applications. We can add what we want in the header and footer of MS Excel sheets.

The branch of biology that studies the different structures and functions of the cell is called Cell Biology or Cytology.

 
Cell biology (formerly called Cytology), is a Greek word: kytos, "vessel" is a branch of biology that studies the different structures and functions of the cell and focuses mainly on the idea of the cell as the basic unit of life.

The cell (from Latin cella, meaning "small room") is the basic

• Structural,

• Functional (and) 

• Biological unit of all known living organisms. 

A cell is the smallest unit of life that can replicate independently, and cells are often called the "building blocks of life". 

A touch screen is the only device which works as both an input and an output device among the given options. You view the options available to you on the screen (output) and you then use your finger to touch the option that you have chosen (input).

Hence, Screen is not purely output device.