1) Ukraine
2) Russia
3) Poland
4) Iran
Explanation:
On July 10, 2019, Ukraine and its European partners have inaugurated the world’s largest new metal dome encasing the destroyed reactor at the infamous Chernobyl nuclear power station. The New Safe Confinement seals the remains of the fourth reactor worth 1.5 billion euro( $1.7 billion, partly funded by the European Bank for Reconstruction and Development (EBRD) and sponsored by 45 countries).Chernobyl plant was the site of the world’s worst nuclear civilian accident on April 26, 1986, when Reactor 4 exploded, killing at least 30 people.350,000 people were evacuated from within a 30-kilometer radius around the plant.