It is unlikely that Mars will ever be colonised by humans, since the journey to and from Mars would be long and frought with too many dangers. Also, Mars is too far from the Sun to have a good living temperature, and atmospheric conditions would be adverse.
No. The planet we are most likely to colonize is Mars.
Probably.
No. The planet we are most likely to colonize is Mars.
Exploration and perhaps to colonize in the future. With an atmosphere it is the most habitable of all others in our system.
If you could take plants to Mars without them dying, it would help making Mars a planet that can support an ecosystem. Plants produce Oxygen which is crucial for animal survival (this includes humans, too, because technically humans are a type of animal). If Mars could successfully support an ecosystem, we could colonize it, which would help resolve issues with overpopulation.
A long time and a lot of money.
The talents needed to colonize a planet would depend upon which planet you are colonizing. Some are harder to colonize than others, and in any event, this is a very hypothetical question since we are not remotely capable of colonizing any planet at this time in human history. Mars would be the best bet, but we really are not prepared to make the kind of investment that would be needed to colonize Mars (although I understand that some people want to fund a trip to Mars as a reality TV program, something like Survivor Mars - it is doubtful that this could result in a self-sustaining colony, but who know). So let's say you are going to colonize Mars. This is not easy to do since Mars does not have a breathable atmosphere. It would require massive technological support to colonize a planet like Mars, and that in turn means that the talents you need lie in the field of science and technology. You have to be able to build and maintain very sophisticated machinery, and if you don't do that, you will run out of air and will die. It's a serious business.
they would die
There will never be a rush to colonize Mars as the place is very unattractive in most properties: no air, no water, no concentrated minerals, little heat, little exploitable energy. A colony on Mars would be heavily dependent on outside support and would (probably) never become self-sufficient. Colonists would be condemned to live in sealed containers for their entire life.
Not likely.
Not likely.