A.
In the first generation we have 2 ancestors.
In the second generation we have 4 ancestors or

ancestors.
In the third generation we have 8 ancestors ot

ancestors.
We can see that each succesive generation has two times more members. The sum is:

To calculate number of ancestors we can use formula <span>for the sum of a geometric sequence. Geometric sequence is sequence of numbers that differ by a certain factor. This factor is called ratio. Formula is:
</span>

<span>Where:
S -> sum
a1 -> first member of a sequence
r -> ratio
n -> number of elements
For this question:
a1 = 2
r = 2
n = 40
</span>

<span>
b.
1 generation = 25 years
40 generations = 40 * 25 = 1000 years
c.
Total number of people who have ever lived = </span>

Number of ancestors in 40 generations =

The number of ancestors is greater than total number of people who have ever lived. This means that not all ancestors were distinct and that in each generation both men and women had children with more than one partner.
Answer:
$7
Step-by-step explanation:
To solve this one we will subtract how much he spends from what he has. At the start he had 19 and then spent 8 meaning he now has 8 less than when we started so 19-8 is 11. He now as 11 dollars, then he spend another 4 meaning we have to subtract another 4 dollars. 11-4 is 7. So he as 7 dollars left at the end.
I hope this helps and please don't hesitate to ask if there is anything still unclear!
Answer:
(3,4)
Step by step explanation:
Given:
The two functions are:


To find:
The function
.
Solution:
We have,


Now,


Therefore, the correct option is B.
Let's create an equation to find the # of weeks until Chad learns 937 pieces.
x = # of weeks
937 = 2x + 805
Subtract 805 from both sides.
132 = 2x
Divide both sides by 2
66 = x
Chad will need 66 weeks of lessons to learn 937 pieces.