I'm sorry I'm too lazy to read all of that. However, I did get the main point. The river was going at 3 mph. Since he wanted to travel 10 miles upstream and downstream, you would have to subtract 20 by 3. This would mean he was going at a speed of 17 mph.
Answer:

Step-by-step explanation:
This shape is called a rectangular prism. The formula for finding the volume of this prism is: 
All you do is plug the values into the formula.
The length is 2m
The width is 1m
the height is 5m
Volume = (2m)(1m)(5m)
Volume = 
Answer: The angles of ΔA'B'C are congruent to the corresponding parts of the original triangle.
Step-by-step explanation:
Given : Triangle ABC was rotated 90 degrees clockwise. Then it underwent a dilation centered at the origin with a scale factor of 4.
A rotation is a rigid transformation that creates congruent images but dilation is not a rigid transformation, it creates similar images but not congruent.
Also, the corresponding angles of similar triangles are congruent.
Therefore, The angles of ΔA'B'C are congruent to the corresponding parts of the original triangle.