question: and insist upon that a computer is nothing but a new tool.
Capitalize this past sentence correctly.
A: And insist upon that a computer is nothing but a new tool.

question: many of the movies that are available online and the videos that are captured from various dslr cameras are in .mov format.
Capitalize this past sentence correctly.
A: Many of the movies that are available online and the videos that are captured from various DSLR cameras are in .mov format.

question: plants have sophisticated mechanisms to deal with free radicals.
Capitalize this past sentence correctly.
A: Plants have sophisticated mechanisms to deal with free radicals.