1. I'l marks) The Chernobyl nllclear plant explosion occurred on April 26, 1986. One of thc main reasons that thc area has not been re-inhabited has to do with thc release of 24 kilograms of Caesium-137 into thc earth. If thc half-life of Caesi11m-137 is 30 years, how rnllch of it wa:s present on October 26, 2021 (i.e. yesterday)? Result may bc rounded to 2 decimal places.