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.
14 Molar is its molarity.
Answer:
, 
Explanation:
The change in energy is given by the change in gravitational potential energy:



The average rate of change in terms of time is approximately this:



Answer:
1. negative
2. positive
3. neutral
Explanation:
Ok so it looks like they are asking for the charge (positive, negative, or neutral) of each thing
So for 1, it would be negative, because it's pointing to an electron. Electrons always have a negative charge.
So for 2, it would be positive, because it's pointing to a proton. Protons always have a positive charge
So for 3, it would be neutral, because it's pointing to a neutron. Neutrons always have a neutral charge.
Answer:
Yes
Explanation:
because some foods have carbohydrates but are healthy