Our weekly news round-up: Elon Musk backs #deletefacebook campaign by taking down Tesla and SpaceX pages; Tim Cook tells China Development Forum new regulations are needed to protect privacy online; Australia to deploy wind and solar powered ocean research drones; Great Pacific Garbage Patch far bigger than previously thought; Millions of Spotify users have ad blockers to avoid paying for the service; Smart farms showcased in Sydney; Google Chrome cracks down on autoplay video ads; Samsung Pay connects Australia's big banks into its NFC payment system.