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.
Cytokinesis and telophase!
Magnesium oxide is an ionic compound with a very high melting point and which requires a large amount of energy for melting.
<h3>What are ionic compounds?</h3>
Ionic compounds are compounds which are formed between oppositely charged ions which are held together by electrostatic forces of attraction between the oppositely charged ions.
Ionic compounds are formed when metal atoms donate electrons to non-metals atoms to form ions.
Magnesium oxide is an ionic compound.
The nature of bonding is ionic bonding.
It has a crystalline lattice structure.
The forces of attraction is electrostatic forces of attraction.
It has a high melting point of 2,852 °C, and thus requires a large amount of energy go melting to occur.
Therefore, magnesium oxide is an ionic compound which requires a large amount of energy for melting.
Learn more about ionic compounds at: brainly.com/question/11638999
Is true. Nitrogen gas behaves more like an ideal gas as the
temperature increases. Under normal conditions such as normal pressure and temperature
conditions , most real gases behave qualitatively as an ideal gas. Many
gases such as air , nitrogen , oxygen ,hydrogen , noble gases , and some heavy
gases such as carbon dioxide can be treated as ideal gases within a reasonable tolerance. Generally,
the removal of ideal gas conditions tends to be lower at higher temperatures and lower density (that is at lower pressure ), since the work made by the intermolecular
forces is less important compared to the kinetic energy<span> of the particles, and the size of the molecules is less important
compared to the empty space between them. </span><span>The ideal gas model
tends to fail at lower temperatures or at high pressures, when intermolecular
forces and intermolecular size are important.</span>
