Answer:
The correct option is (d)-He wrote commutative instead of associative in Step 2.
Step-by-step explanation:
Commutative property: 
Associative property: 
Now consider the provided expression.
(6.2 − 1.6) − 4.4 + 7.8
Step 1
(6.2 − 1.6) − 4.4 + 7.8
Step 2 Use Associative property
6.2 + (−1.6 − 4.4) + 7.8
Step 3: Simplify
6.2 − 6 + 7.8
Step 4: Use commutative property
14 − 6
Step 5: Simplify
14 − 6 = 8
Hence, the wrong step is step 2. He wrote commutative instead of associative in Step 2.
Therefore, the correct option is (d)-He wrote commutative instead of associative in Step 2.
Answer:
B
Step-by-step explanation:
This is proportional because the number of calories burned is directly proportional to the amount of time spent on the treadmill
Answer:
The number of subscribers in 2008 is 110,845,988
Step-by-step explanation:
The number of cell phone subscribers in Arlington, in t years after 1985, can be modeled by the following equation.
And which N(0) is the number of subscribers in 1985 and r is the rate it increases per year, as a decimal.
In 1985, there were 285 cell phone subscribers in Arlington.
This means that 
The number of subscribers increased by 75% per year since 1985.
This means that 
So
Find the number of subscribers in 2008.
2008 is 2008-1985 = 23 years after 1985. So we have to find N(23).
The number of subscribers in 2008 is 110,845,988
The slope should be
m= 2/3 (2 over 3)
Second question:
sum of all the interior angle 180*(8-2)=1080 degree
sum of one interior angle 1080/8=135 degree
