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In their quest to discover something that doesn't exist, Phineas and Ferb have invented unobtanium (Ub) a new element, w

  1. In their quest to discover something that doesn't exist, Phineas and Ferb have invented unobtanium (Ub) a new element, with a half life of 12 days, atomic weight 40 and atomic number 20.
    1. If this were an alpha emitter, would it be dangerous outside your body?
    2. What about if you breathed it in? why?
    3. A 440 gram sample of Ub40 (joke there) decays for 36 days. How much is left?
    4. Another sample is found to have 1/64 of the original amount. How old is it?
    5. How many protons in Ub40?
    6. How many electrons?
    7. How many neutrons?
  2. While giving a monkey a shower, Ferb discovers that fleas on the monkey multiply rapidly, doubling every 24 hours.
    1. If the monkey initially has 4 fleas, how many would there be after 3 days?
    2. If the monkey started with 16 fleas, how many would there be after 3 days?
    3. If the growth rate for the fleas is 7%, what would be the doubling time (use the rule of 70 formula, even though it usually means per year)?
    4. If the growth rate were 35%, what would be the doubling time?
  3. Candace discovers that Phineas has been playing hide and seek with radioactive items, hiding them in places that she can't find. She uses a geiger counter to look for radiation.
    1. If she finds an alpha source, what could have hidden this?
    2. If she finds a beta source, what could have hidden this?
    3. If she finds a gamma source, what could have blocked these rays?
    4. What about neutrons?