Answer:
1.6 ft/min
Explanation:
Since trough is 10 ft long and water is filled at the rate of 12ft3/min. We can calculate the rate of water filled with respect to area:
= 12 / 10 = 1.2ft2/min
As the water level rises, so does the water surface, or the bottom side of the isosceles triangles. In fact we can calculate the bottom side when the trough is half foot deep:
= 3 / 2 = 1.5 ft
The rate of change in water level would be the same as calculating the height of the isosceles triangles knowing its base
= 1.2 * 2 / 1.5 = 1.6 ft/min
The answer is C. Electrical;mechanical
Answer:
Total internal reflection is going on. The refractive index of water is about 1.3, so sin 90/sin r=1/sinr=1.3. So the fish can only see objects outside the water within about 50 degrees of the vertical
D - Most likely. Those who read the magazine can choose whether or not to return the survey.