Given that,
The equation is : 
To find,
The missing coefficients.
Solution,

Let the value of ? is x.
It is the equation of photosynthesis.
In LHS,
Carbon atoms = 6
Hydrogen atom = 12
Oxygen atom = 18
In RHS,
Carbon atoms = 6
Hydrogen atom = 12
Oxygen atom = 6
If we make the equation as 
No the number of atoms in RHS = 6+ 12 = 18
It means if we take the value of ? as 6 the equation will be balanced.
Hence, the correct option is (B) "6".
Answer: 31 (a) 4 32 (a) 5
(b) 7 (b) 3
(c) 5 (c) 5
(d) 3 (d) 2
<u>Significant Figures (sf) Rules:</u>
1) Trailing zeroes are considered significant ONLY If a decimal point is provided.
2) Zeroes between the decimal point and number are NOT significant <u>unless</u> they are between numbers.
3) All digits in scientific notation are counted (disregard the exponent).
31 (a) 508.0 <em>trailing zero so use rule 1 </em> --> sf = 4
(b) 820,400.0 <em>trailing zero so use rule 1 </em> --> sf = 7
(c) 1.0200 x 10⁵ <em>scientific notation so use rule 3</em> --> sf = 5
(d) 807,000 <em>no trailing zeroes so use rule 1</em> --> sf = 3
32 (a) 0.049450 <em>zero between decimal point & #, use rule 2</em> --> sf = 5
(b) 0.000482 <em>zero between decimal point & #, use rule 2</em> --> sf = 3
(c) 3.1587 x 10 ⁻⁸ <em>scientific notation so use rule 3</em> --> sf = 5
(d) 0.0084 <em>zero between decimal point & #, use rule 2</em> --> sf = 2
Answer:
gravity
Explanation:
your mass is the same on the moon as is on earth or underwater but your weight changes because of gravity
1. 4 Layer of the sun that is known for its red color and can only be seen during eclipses
2. 3 contains the sun’s outer shell from which light energy is radiated
3. 2 layer of the sun where energy is transferred by thermal conduction
4. 1 the plasma that surrounds the sun