Answer:
Part A. At least 6 hours
Part B. In less than 2.5 hours Elijah will be behind Mercedes
Part C. In more than 2.5 hours Elijah will be ahead Aubrey
Step-by-step explanation:
D = distance
v =speed
t = time
Formula connecting D, v and t:

Part A.
Steve's speed: 
Distance: at least 21 miles
Time: unknown, so
![3.5\cdot t\ge 21\\ \\35t\ge 210\ [\text{Multiplied by 10}]\\ \\t\ge \dfrac{210}{35}\\ \\t\ge \dfrac{30}{5}\\ \\t\ge 6](https://tex.z-dn.net/?f=3.5%5Ccdot%20t%5Cge%2021%5C%5C%20%5C%5C35t%5Cge%20210%5C%20%5B%5Ctext%7BMultiplied%20by%2010%7D%5D%5C%5C%20%5C%5Ct%5Cge%20%5Cdfrac%7B210%7D%7B35%7D%5C%5C%20%5C%5Ct%5Cge%20%5Cdfrac%7B30%7D%7B5%7D%5C%5C%20%5C%5Ct%5Cge%206)
It would take Steve at least 6 hours to walk at least 21 mi on Day 1.
Part B.
Mercedes's speed: 
Elijan's speed: 
Elijan's Distance walked:
miles
Mercedes's Distance walked:
miles
Time: x hours
Mercedes is 2 miles ahead, so

Elijan will be behind when

In 2.5 hours Elijan will catch up Mercedes, and in less than 2.5 hours Elijah will be behind Mercedes.
Part C.
Aubrey's speed: 
Elijan's speed: 
Elijan's Distance walked:
miles
Aubrey's Distance walked:
miles
Time: x hours
At the beginning of Day 3, Elijah starts walking at the marker for Mile 42, and Aubrey starts walking at the marker for Mile 42.5.

Elijan will be ahead of Aubrey when
![D_E>D_A\\ \\42+3.2x> 42.5+3x\\ \\3.2x-3x>42.5-42\\ \\0.2x>0.5\\ \\2x>5\ [\text{Multiplied by 10}]\\ \\x>\dfrac{5}{2}\\ \\x>2.5\ hours](https://tex.z-dn.net/?f=D_E%3ED_A%5C%5C%20%5C%5C42%2B3.2x%3E%2042.5%2B3x%5C%5C%20%5C%5C3.2x-3x%3E42.5-42%5C%5C%20%5C%5C0.2x%3E0.5%5C%5C%20%5C%5C2x%3E5%5C%20%5B%5Ctext%7BMultiplied%20by%2010%7D%5D%5C%5C%20%5C%5Cx%3E%5Cdfrac%7B5%7D%7B2%7D%5C%5C%20%5C%5Cx%3E2.5%5C%20hours)
In 2.5 hours Elijan will catch up Aubrey, and in more than 2.5 hours Elijah will be ahead Aubrey.
Answer:
1.
2.
and 
3. 
Example: 
Step-by-step explanation:
1. We have
, and we have to prove that this term is equivalent to
.
Now,
=
{Since we know the property of exponent as
}
=
=
2.
and
3. The power of products property gives
........ (1)
For example, we can write, 
Answer:
3(x-1)
Step-by-step explanation:
you need to out the x minus 1 in brackets as you multiply the whole thing by 3
Hey there!
The account earns 2.5% interest.
To figure out if it earns simple or compound interest, we need to figure out if the interest earned each year, simple, is the same amount or if it's increasing each year, compound.
512.50 - 500 = 12.50
525.31 - 512.50 = 12.81
538.44 - 525.31 = 13.13
Simple interest is based on the principal amount, so the amount earned each time is the same. But in compound interest, the interest previously earned is added before calculating the next period's interest, so the amount of interest earned each period is different.
So, this is a compound interest.
Hope this helps!