Using the slope concept, it is found that the boat traveled at a speed of 138 feet per minute.
What is a slope?
The slope is given by the vertical change divided by the horizontal change, and it's also the tangent of the angle of depression.
At point A, we have that the vertical change is of 245 ft with an angle of 12º, hence the position in feet is given by:
[tex]\tan{12^\circ} = \frac{245}{x_A}[/tex]
[tex]x_A = \frac{245}{\tan{12^\circ}}[/tex]
[tex]x_A = 1152.6[/tex]
At point B, we have an angle of 28º, hence:
[tex]\tan{28^\circ} = \frac{245}{x_B}[/tex]
[tex]x_B = \frac{245}{\tan{28^\circ}}[/tex]
[tex]x_B = 460.7[/tex]
The distance in feet the boat traveled in 5 minutes was of:
[tex]d = x_A - x_B = 1152.6 - 460.8 = 691.8[/tex]
Velocity is distance divided by time, hence:
v = 691.8/5 = 138.
The boat traveled at a speed of 138 feet per minute.
More can be learned about the slope concept at https://brainly.com/question/18090623