I would think it is a heterogeneous mixture since it can't be an element since there are more than one type of atom, it can't be a compound since the leaves are not bonded together, and it can not be a homogeneous mixture since the leaves don't all blended together (the pile is not uniform) and you can distinguish all the different parts of the mixture. It can be considered a heterogeneous mixture since the leaves are mixed together (along with other things like dirt) in a non-uniform way so that you can point out the parts of the mixture and it does not look like one thing.
I hope this helps. Let me know in the comments if anything is unclear.
Answer:
The diagram on the right. It has increments of 0.1 of a unit and therefore will provide a more precise measurement. The diagram on the right measures 88.4. In terms of the diagram on the left, a decimal answer cannot be determined because the increments are too large. Therefore the diagram on the left is less precise.
Answer:1) Volume of
required is 55.98 mL.
2) 0.62577 grams of
is produced.
Explanation:

1) Molarity of 
Volume of 
Molarity of 
Volume of 


According to reaction, 1 mole of
reacts with 3 mole of
, then, 0.0041985 moles of
will react with:
moles of
that is 0.0125955 moles.


Volume of
required is 55.98 mL.
2)

Number of moles of
According to reaction, 3 moles of
gives 1 mole of
, then 0.004485 moles of
will give:
moles of
that is 0.001495 moles.
Mass of
=
Moles of
× Molar Mass of 
= 0.001495 moles × 418.58 g/mol = 0.62577 g
0.62577 grams of
is produced.