Why lanthanides and actinides series are situated at the buttom of the periodic table

Consider the nuclear equation below. 239/94 pu—-> x+ 4/2 he. what is x?

What is the temperature of one mole of helium gas at stp?

Which are examples of how technology has advanced scientific understanding.1using hot water to sterilize medical equipment.2transplanting a human organ into another individual.3inserting genes from one sheep into another cell to make a cloneunderstanding the different structures that make up a cell.4examining microorganisms from the deepest parts of the ocean