Electric vehicles, 600 million bottles and does oral sex cause cancer?

There's been a lot of coverage about the risks electric cars may pose to infrastructure like bridges and car parks. We look at how much heavier EVs are. Plus we look at a new study that suggests a link between breastfeeding and improved grades at GCSE level. Also is throat cancer now primarily caused by a sexually transmitted disease - and are 600 million bottles going to litter Scotland because of disagreements with the UK government over the new Deposit Return Scheme?

Presenter: Tim Harford Series producer: Jon Bithrey Reporters: Jo Casserly, Nathan Gower, Charlotte McDonald Editor: Richard Vadon Sound Engineer: James Beard Production Co-ordinator: Brenda Brown