I read on the US Environment Protection Agency website, that using a petrol lawn mower produces more carbon dioxide in an hour than a car produces whilst covering 300 miles. I had assumed that, when burning petrol, all of the carbon combines with oxygen in the air so the co2 produced varies in proportion to the amount of fuel burnt? What have I missed?

Simon Forbes

Hove

During a walk last Easter to the Summit of Mt Kosciuszko (Australia's highest mountain) I  was suprised to spot some fish swimming in a small pool approximately 200M from the top of the mountain. The pool appeared to be a small man-made drainage channel that drained under the walkway. My question is how did the possibly get there? The mountain is covered in freezing snow for most of the winter months (July - September) so I thought it unlikely that they woud survive. They cannot have existed there since day dot. Did someone put them there?