The blue circle has radius 2 and the green circle has radius 1 AB is a common tangent and all 3 circles touch each other. Find the radius of the smallest circle. The answer is btw 6 - 4√2 how ever I'm only getting as to far as (6-2√2)/7 Please solve with working

I'm confused on this could anyone me and show me what i need to do to solve it.

Ascientist has discovered an organism that produces five offspring exactly one hour after its own birth, and then goes on to live for one week without producing any additional offspring. each replicated organism also replicates at the same rate. at hour one, there is one organism. at hour two, there are five more organisms. how many total organisms are there at hour seven? 2,801 19,531 19,607 97.655

Answer asap evaluate 4-0.25g+0.5h4−0.25g+0.5h when g=10g=10 and h=5h=5.