How can the human race survive the next hundred years?
I cannot believe you will have the time to read more than 17,000 answers in order to get to this one, but I answer it nonetheless.
Because in posing the question, you have also pointed to the answer.
We know that in order to survive we must reduce our use of resources, we must refrain from global war, we must protect the environment, we must manage in the face of global plagues, and then, if we're lucky, we'll make it.
We are not going to succeed working against each other. We are not going to succeed when we in the west think of China and India as the 'competition' that we have to outperform in order to preserve our way of life.
We need to address the causes of conflict before they start. We need equitable distribution of resources, we need political and social systems that promote harmony, we need freedom and dignity for individuals.
So why do I think this question is important? Because 17,656 people - as of now, three days after the question was posted - have answered.
Because we're going to find (though perhaps only through automated extraction) a great deal of consensus and commonality in the responses.
Because it shows that we want to survive, even if we are not going to be here personally.
This gives me hope.
And that, I think, is where we need to begin. With the desire. With the belief. With the hope.
And then, as so many hundreds of people wrote, well muddle through. Somehow.
Thank you for asking this question, Dr. Hawking, and thank you for the unique opportunity of being able to answer.