Answer: 
Step by step:

(Used a table of common angles)
Answer:
D. 26 m
Step-by-step explanation:
The Fernandez family would have driven 208 miles in a rate of 4 hours.
Answer:
2/5 is less than 2/3
2/5 < 2/3
Step-by-step explanation:
2/5 x 3=6/15 is small
2/3x5=1<u>0/15 is big</u>
Again, nice problem. These are not super easy. You need to imagine the triangles in the figure and relate sides.
For instance: ADC, its hypotenuse is 15
For ABC, it is 20,
so 20/15 is the ratio between both triangles. Now let's choose the side with 'x'
x is one side of ADC, the corresponding side in ABC is 15 (the second longest sides). You need to rotate the triangles, etc ... That's the tricky part :)
So:
20/15 =15/x ----> x = 15*15/20 = 225/20 = 45/4
Which is C
Not sure whether it's too late to help you though!!!!
Also notice that it's kind of a product rule:
x * 20 = 15 * 15
I am sure the book explains a short way of getting to this equation, like sides opposite, blah blah, but what i told you is the reason. You asked for understanding it! Best luck!