Answer:
Earth's far distance from the sun
Explanation:
We have hot summers and cold winters because of the tilt of the Earth's axis. The tilt of the Earth means the Earth will lean towards the Sun (Summer) or lean away from the Sun (Winter) 6 months later.
Answer: 8 moles
Explanation:
Nc2H6= 4 mol
2C2H6 + 7O2 → 4CO2+6H2O
CO2=4/2⋅4
NCO2= 8 moles
( I write this on paper so the letters and format might be confusing) sorry!!
Answer:

Explanation:
Scientific notation is the way of writing numbers which are either large or small. The number is written in the scientific notation when the number is between 1 and 10 and then multiplied by the power of 10. Engineering notation is the same version of the scientific notation but the number can be between 1 and 1000 and in this exponent of the ten is divisible by three.
For example,
is to be written as
in engineering notation.
The given number:
0.00000009345 can be written as 
Answer upto 4 significant digits = 
D, because C12 means there's 12 atoms of carbon.