Why do we have eyebrows? Can we taste food if we can't smell it? What's a cold sore? This week, we take on your science questions, as well as explore the world of social gaming, and find out how much it costs to fly an England flag from your car. We'll be asking if altitude affects how a football flies, if a large enough fan could propel a spacecraft and how spiders spin webs from one tree to the next. Plus, why size matters in bird beaks, how plant roots cope with competition and building lungs in the lab!