Answer:
a. 1 1/8 b. 8/9
Step-by-step explanation:
You can set this up as a proportion to solve. For part a. we know that 2/3 of the road is 3/4 mile long. 2/3 + 1/3 = the whole road, so we need how many miles of the road is 1/3 its length. Set up the proportion like this:

Cross multiplying gives you:

The 3's on the right cancel out nicely, leaving you with

To solve for x, multiply both sides by 3/2:
gives you

That means that the road is still missing 3/8 of a mile til it's finished. The length of the road is found by adding the 3/4 to the 3/8:

So the road is a total of 1 1/8 miles long.
For b. we need to find out how much of 1 1/8 is 1 mile:
1 mile = x * 9/8 and
x = 8/9. When 1 mile of the road is completed, that is 8/9 of the total length of the road completed.
Answer:
Yes
Step-by-step explanation:
Answer:
B 26.3% increase
Step-by-step explanation:
1 - 3.50/4.75 = .263 = 26.3%
ANSWER

EXPLANATION
The explicit rule for an arithmetic sequence is given by:

It was given that:

and

The common difference is

We plug in the values into the explicit formula to get,

Expand to get,

The explicit rule is

As shown in the image, we have a 30 degree angle and x, which is what we want. By doing tan30, we can find x, so tan30=x/70 and 70*tan30=x= 70*sqrt(3)/3. 120-x=height of first tower = 120-(70*sqrt(3)/3) = roughly 79.59