<u>a) Answer: </u>
<em>Number of molecules in 1 mole</em>
<u>Explanation:</u>
a) Whether we take any of the substance among all three of the given substances they will have the same number of molecules in 1 mole of the substance is considered and the value for this will be 
<u>b) Answer: </u>
<em>In the given question </em><em>mass of the substance</em><em> which is </em><em>greatest</em><em> is asked for </em><em>one mole</em><em> and we also know that </em><em>mass of one mole is given by molar mass. </em>
<u>Explanation:</u>
b) It is known that
is the molar mass for oxygen which is greater than that of hydrogen while fluorine has a molar mass of
which on comparison shows that, it is the highest amongst all three.
The inverted cone, hope it helps .
Answer:
The answer is
<h2>4.69 mL</h2>
Explanation:
The volume of a substance when given the density and mass can be found by using the formula

From the question
mass of wood = 4.6 g
density = 0.98 g/mL
It's volume is

We have the final answer as
<h3>4.69 mL</h3>
Hope this helps you
Explanation:
B. The light bends in the water causing the straw to look different.
This happens due to the refraction of light.