Meanwhile, President Donald Trump has told a White House event the US is striking Iranian drone and missile systems "every single hour".

Whale sharks: Atomic tests solve age puzzle of world's largest fish 鲸鲨：原子能试验解开世界上最大鱼类的年龄之谜 Episode 200427 / 27 Apr 2020 How long can these massive sea creatures live? Blood test 'can check for more ...

Uranium (chemical symbol U) is a naturally occurring radioactive element. In its pure form it is a silver-coloured heavy metal, similar to lead, cadmium and tungsten. Like tungsten it is very dense, ...