4. Given a set of 10 balls among which there are exactly 3 radioactive. each test you put any number of balls in a box, push a button and a bulb will be on if there is at least one radioactive ball in the box and will be off otherwise. Using lower bound method tell what is the minimum number of tests is necessary (you cannot do better) to find all 3 radioactive balls. 3EC. Show how to find at least 1 radioactive ball out of 3 radioactive balls from total of 10 balls in 3 tests