I believe your answer is B.
Asteroids are made up of metals and rocky material , while comets are made up of ice ,dust and rocky material.
Answer:
Ionic compound
Explanation:
Lithium gives away an electron and Bromine takes an electron
Hope this helps! :)
Answer:
Cold-blood animals are the animals that are not capable of regulating their body temperature,Cold blood animals included reptiles,fishes,amphibians,insects and other invertebrates.
Answer: half life
Explanation: Radioactive decay follows first order kinetics and the time required for the decay of a radioactive material is calculated as follows:

t= time required
k= disintegration constant
x= amount of substance left after time t
a= initial amount of substance
when one half of the sample is decayed, one half of the sample remains and t can be represented as 
at
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