question: this brings me to the purpose of this article, and that is cleaning up on the internet.
Capitalize this past sentence correctly.
A: This brings me to the purpose of this article, and that is cleaning up on the internet.

question: application samples: reactive nut for through hole applications.
Capitalize this past sentence correctly.
A: Application samples: Reactive nut for through hole applications.

question: we spend about an hour here, but now our backs and feet are sore, so we leave for a cup of coffee.
Capitalize this past sentence correctly.
A: We spend about an hour here, but now our backs and feet are sore, so we leave for a cup of coffee.