Coral is sometimes used to replace human bone
ANSWER
EXPLANATION
The sum of the first 
terms of a geometric sequence is given by;
Where , is the number of terms and 
is the first term.
When 
, we have 
, we get;
Don't know try something else it will probably help
Five million,Nine hundred and twenty thousand, One hundred seventy eight
Answer:
2a²
Step-by-step explanation:
Pair 'like' terms with 'like' terms, ie numbers go with numbers, and 'a's go with 'a's.
Lets deal with the top of the fraction first:
4ax3a³
Rearrange it so you have numbers beside numbers and 'a's beside 'a's:
(4x3)x(axa³)
12x(a⁴) <em>(because nᵃxnᵇ=nᵃ⁺ᵇ)</em>
12a⁴
Now, instead of (4ax3a³)/6a², we have 12a⁴/6a²
First divide the numbers: 12/6 =2
Now divide the 'a' parts: a⁴/a²=a² <em>(because nᵃ/nᵇ=nᵃ⁻ᵇ)</em>
Now we have 2a²
