Please: Only 5 minutes to answer :( 1: Why do we need to know the "Launch Window" for Mars?
It is when the correct side of Mars is facing the earth
It is during the Mars winter
It is when earth and Mars are closest together
It is when the cheapest airfares to Mars are available.

2: Why is it important to find Hydrogen and Carbon Dioxide on Mars.
So we can communicate with Earth
So we can have pollution on Mars when we get there.
So we can produce breathable air , fuel and water
So we can drive solar cars