Please capitalize where necessary: who are we, what are our challenges, and how do we meet them?
A: Who are we, what are our challenges, and how do we meet them?

Q: together with zehnder, he published fixed point results for symplectic maps related to the arnol'd conjecture in the proceedings of the conference dynamical systems and bifurcations held in groningen in 1984.

A: Together with Zehnder, he published Fixed point results for symplectic maps related to the Arnol'd conjecture in the Proceedings of the conference Dynamical systems and bifurcations held in Groningen in 1984.

Q: this trend does not really exist in champagne, known as one of the coolest regions of france.
A: This trend does not really exist in Champagne, known as one of the coolest regions of France.

Problem: did someone email you a egd file and you're not sure how to open it? maybe you have found a egd file on your computer and wondering what it's for? windows might tell you that you can't open it, or in the worst case, you might encounter a egd file related error message.
Can you repeat this sentence, but capitalize it?
Answer: Did someone email you a EGD file and you're not sure how to open it? Maybe you have found a EGD file on your computer and wondering what it's for? Windows might tell you that you can't open it, or in the worst case, you might encounter a EGD file related error message.

Text: there has been prepared preliminary concepts for nitrogen supply (fertilization) and weed (and prevention) based on existing models and the above synthesis.

Correct capitalization: There has been prepared preliminary concepts for nitrogen supply (fertilization) and weed (and prevention) based on existing models and the above synthesis.

Problem: using down house, which was darwin's home for the majority of his life as well as the place where he wrote on the origin of species, as the backdrop, doherty invites viewers to join a rarely empathetic and completely amazing rendition of many of darwin's experiments.
Can you repeat this sentence, but capitalize it?
Answer:
Using Down House, which was Darwin's home for the majority of his life as well as the place where he wrote On the Origin of Species, as the backdrop, Doherty invites viewers to join a rarely empathetic and completely amazing rendition of many of Darwin's experiments.