Answer:
I think it's b if not then sorry
Answer: It is C I just did this question in math class
Explanation:
Answer : Half reaction is defined as the reaction which will be <span>either the oxidation or reduction </span>reaction<span> of particular species in a given redox </span>reaction<span>.
So as per the definition in the reaction of,
</span>

<span>
</span>

<span>
here on left and right side </span>

will get cancelled.
and we will get,

Here,

...this is oxidation reaction as Ba is getting reduced to

by losing 2 electrons.
whereas,on the other hand,

...this is reduction reaction as

is getting reduced to Zn by gaining 2 electrons.
Answer: B. They reproduce slower than unicellular organisms
Explanation:
In unicellular organisms there is a single cell which performs all the functions like digestion, respiration, and reproduction. The cell reproduce by cell division. The single parent cell divides into two identical daughter cells. But multicellular organisms exhibit multiple cells and their reproduction is complex. They reproduce by sexual mode of reproduction in which separate sex cells are produced when they fuse form zygote which is the precursor of new organism. This process is slower than that of the cell division and production of progeny by the unicellular organisms. Thus reproduction is slower in multicellular organism this is the disadvantage in multicellular organisms.