The answer is c hope this helps
A). very large
B). very small
These are both wishy-washy words ... words that mean different things
to different people, and may even mean different things to the same person
at different times.
Even if everybody agreed on the meaning of these words, we wouldn't
have any idea which one may apply to the rover, because there's nothing
in the picture that gives any size reference ! We don't know from the picture
whether this thing is the size of a school book or a school bus. Or somewhere
in between.
C). very mathematical
What in the world does this mean ? ?
I don't see a single number or math symbol anywhere in the drawing.
I don't think this is the correct choice.
D). very complex
In the drawing, there are thirteen different labels of things,
and eight of them have such long names that only their initials
are shown.
This is one complicated combination of many different machines.
I think this is the best choice of description.
Answer:
3.71 m/s
Explanation:
From the law of conservation of linear momentum, since we are neglecting minor energy losses due to friction then we can express it as 
since all the potential energy is transformed to kinetic energy
Making v the subject of the formula then 
and here m is the mass of the block, g is acceleration due to gravity, h is the height. Substituting 0.7 m for h and 9.81 for g then we obtain that 
Use of lubricant
Use of ball bearers
Use of streamlined body
Use of graphite
-- 'Ca' (Calcium) is an element.
-- The proton has a positive charge.
-- Nuclear fusion results in the synthesis of atoms of new elements.
-- H₂O (water) is a chemical compound.
-- Nuclear fission is a decay of the nucleus.
-- The atomic number of an element is the number of protons
in each atom of it.
-- I suppose you're using the Greek letter <span>η ('eta', not 'nu')
to represent the neutron.
-- I suppose you're using ' e ' to represent the electron.
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