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Q: By Marianna SpringSpecialist disinformation reporter, BBC News The adverts show the Democratic Party challenger with an earpiece, and say that he refused to have his ears checked for devices prior to the debate. The Biden campaign rejected the claims. The Trump campaign adverts ask: "Why won't Sleepy Joe commit to an ear test?" and "Who is in Joe's ear?" Accusations that presidential candidates have received debate help via hidden hearing devices are familiar, albeit unproven. Such allegations have been levelled against both Republican and Democratic candidates in the past. Prior to Tuesday's debate, the rumour about Mr Biden's supposed earpiece was circulating on several social networks, and was being promoted by the Trump campaign. At least 15 versions The advertising campaign was launched after the debate, and also promotes two other baseless but widely shared rumours about Mr Biden. One suggested he asked for breaks during the debate, and another accused him of refusing a "drug test". The photo featured in the advert is not from Tuesday's debate. It was first shared online in September 2019. In a number of the adverts, it has been doctored to show Mr Biden wearing wireless Apple headphones. This was not the case in the original image. Some versions circle the ear featuring the headphone. By Wednesday evening, there were at least 15 different versions of the advert, and according to Facebook's Ad Library, they had reached at least 10 million users. Facebook has pledged to label posts containing voting misinformation and point users towards accurate information ahead of the election. However its policy does not involve fact-checking political speech, including in advertisements. The company declined to comment about the latest Trump ad campaign. Rumour origins Hours before the debate, the claims went viral on Facebook and YouTube. Identical memes were pushed by a number of popular Facebook pages with names such as US Conservative and Unhinged Left. They claimed "Joe Biden should be inspected for a hidden earpiece as well as submit to a drug test before the debate". These memes are subject to fact-checks - and some have had warning labels applied to them on Facebook. The claims were picked up by Fox News and other conservative news outlets. They were further amplified by supporters of QAnon, an unfounded a conspiracy theory that claims President Trump is fighting a secret war against elite Satan-worshipping paedophiles. Those who believe in QAnon are known for promoting political disinformation on social media which targets opponents of the president. They shared close-up pictures of Mr Biden's ears, alleging a listening device was visible. During the debate, some also shared photos of a fold in Mr Biden's shirt, claiming it was caused by a wire, and of a supposed device on his wrist, where he wears a rosary in memory of his late son Beau. Nothing new Conspiracy theories about secret listening devices have been recycled in presidential election campaigns for the past two decades. Democratic candidate Hillary Clinton faced similar unfounded claims ahead of the 2016 presidential election. In 2004, rumours circulated among left-wing sites and blogs that President George W Bush was being aided by a secret earpiece. None of those allegations were found to be true. Even if a candidate did wear an earpiece, any advantage would be questionable. As TV and radio presenters can attest, listening to someone while simultaneously talking during the back-and-forth of a live event is a difficult skill to master.
A: US President Donald Trump's re-election campaign is running hundreds of Facebook advertisements pushing an unfounded conspiracy theory that Joe Biden cheated during the first US presidential debate.
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Q: The decision to cut staff was made on Friday, but Mr Putin has now confirmed the number who must go by 1 September. It brings staff levels to 455, the same as Russia's complement in Washington. This is thought to be the largest action against diplomatic staff from any country in modern history, says the BBC's Laura Bicker in Washington. The number includes Russian employees of the US diplomatic missions across Russia, the BBC's Sarah Rainsford in Moscow adds. Staff in the embassy in Moscow as well as the consulates in Ekaterinburg, Vladivostok and St Petersburg are affected, she says. The US said the move was a "regrettable and uncalled for act". "We are assessing the impact of such a limitation and how we will respond to it," a state department official said. It is not known exactly how many US citizens are employed in the diplomatic missions currently. However, a State Department Inspector General's report in 2013 said more than 900 staff members were "local hires", with only 301 "direct-hire" staff, meaning it seems likely a far lower number than 755 will be actually forced to leave Russia. Mr Putin did strike a conciliatory note, saying he did not want to impose more measures, but also said he could not see ties changing "anytime soon". Mr Putin told Russian television: "More than 1,000 people were working and are still working" at the US embassy and consulates, and that "755 people must stop their activities in Russia". Russia has also said it is seizing holiday properties and a warehouse used by US diplomats. Mr Putin suggested he could consider more measures, but said: "I am against it as of today." He also noted the creation of a de-escalation zone in southern Syria as an example of a concrete result of working together. However, in terms of general relations, he added: "We have waited long enough, hoping that the situation would perhaps change for the better. "But it seems that even if the situation is changing, it's not for anytime soon." Analysis: Russian hopes dashed by Jonathan Marcus, BBC News, defence and diplomatic correspondent Russia hoped for a change in the climate; one where the lifting of many of the western sanctions imposed after its annexation of Crimea might become possible. But more than this, it wanted a new deal between the US and Russia that would acknowledge Moscow as an equal diplomatic player and indeed as a partner in trouble spots, such as Syria, and in the wider struggle against Islamist terror. These hopes have now come to nothing. Russia seems to have placed unrealistic hopes in what President Trump might achieve. Did Mr Putin see him as a forceful like-minded character, or as a political and diplomatic lightweight that might be manipulated and dominated? Either way Russia's own actions in intruding into the US political space and the subsequent investigations, have precluded any fresh start. Russia perhaps failed to understand the Congressional hostility to its activities, mistaking the Trump insiders' lack of concern for the predominant view of the president's supporters on Capitol Hill. Read more: The US and Russia: An uncertain path The new US sanctions were in retaliation both for Russia's annexation of Crimea in 2014 and Russian interference in the US election. In December, the Obama administration ordered the seizure of two Russian diplomatic compounds and expelled 35 Russian diplomats in response to alleged hacking of the US Democratic Party and Hillary Clinton's campaign. The new US sanctions on Russia were overwhelmingly approved by both houses of Congress, despite objections from President Donald Trump who wants warmer ties between the two countries. The White House said on Friday that he would sign the sanctions bill after fears he could veto it. Mr Trump was believed to be particularly concerned about a provision in the new bill that limits his ability to lift sanctions - forcing him to consult Congress first. Some European countries are also angry because the new law could penalise European companies that invest in big Russian oil and gas projects such as the new Nord Stream II pipeline. US intelligence agencies believe Russia tried to sway the election in favour of Mr Trump and now there are several investigations looking into whether anyone from his campaign helped. Russia has always denied interfering and Mr Trump insists there was no collusion. Get news from the BBC in your inbox, each weekday morning
A:
Russian President Vladimir Putin has announced that 755 staff must leave US diplomatic missions, in retaliation for new US sanctions against Moscow.