I think that the answer is d
Answer: (E) 300 bq
Explanation:
Half life is the amount of time taken by a radioactive material to decay to half of its original value.
Radioactive decay process is a type of process in which a less stable nuclei decomposes to a stable nuclei by releasing some radiations or particles like alpha, beta particles or gamma-radiations. The radioactive decay follows first order kinetics.
Half life is represented by 
Half life of Thallium-208 = 3.053 min
Thus after 9 minutes , three half lives will be passed, after ist half life, the activity would be reduced to half of original i.e. 
, after second half life, the activity would be reduced to half of 1200 i.e. 
, and after third half life, the activity would be reduced to half of 600 i.e. 
,
Thus the activity 9 minutes later is 300 bq.
1. How is the modern periodic table organized? Increasing atomic number
2. What information about an atom's properties can you read from the periodic table? Metal or not metal. Does it want to gain or lose electrons
3. How are the relationships of elements in a group different from the relationships of elements in a period? a group will have similar properties A period will have different properties
4. Would you expect Strontium (Sr) to be more like potassium (K) or bromine (Br)?
potassium
5. Barium (Ba) is in Group 2. Recall that atoms in Group 1 lose one electron to form ions with a 1+ charge. What type of ion does barium form? Ba+2
Answer:
Cardiovascular system
also known as the The circulatory system,
Explanation:
please mark branliest if this helped and rate
<span>Friction creates heat which in turn can lead to deviations from the original size and shape of a part.
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