ANSWER
EXPLANATION
The given angle is 870°.
870°-360°-360°=150°
This means that:
870° is coterminal with 150°, hence its terminal side is in the second quadrant.
It makes an acute angle of 30° with the x-axis.
Note that cotangent is negative in the second quadrant,
Hence,
The first option is correct.
We need to estimate how tall is, on average, one of these object, and then count how many would be in a 5 feet high stack.
For example, on Google you may see that "1.5 cubic foot boxes are the standard box, manufactured by most companies". So, we assume that a standard cardboard box is 1.5 feet tall.
So, if we set the equation
So, there would be between 3 and 4 cardboard boxes in a 5 feet tall stack.
Similarly, we can see that the average book is 9 inches tall. 9 inches are 0.75
feet, so we have
So, there would be between 6 and 7 books in a 5 feet tall stack.
The average brick is 75 millimeters tall, which means 0.25 feet tall. Again, we have
So, there would be 20 bricks in a 5 feet tall stack.
Finally, a coin is about 0.006 feet, which leads to
So, there would be between 833 and 834 coins in a 5 feet tall stack.