see the attached figure to better understand the problem
we know that
The equilateral triangle has three equal sides
so
in the equilateral triangle ABC

the height of the triangle is the segment BD
in the right triangle BCD
Applying the Pythagorean Theorem

solve for BD

substitute the values



therefore
<u>the answer is</u>
the height of the triangle is 
21^2/0.219 = 2013.69863
2 significant figures are the 20, so the answer is 2000
Answer:
1.33
Step-by-step explanation:
The z-score of a value is found by subtracting the mean from the value and then dividing by the standard deviation, this is the formula for the z-score.
z-score = (19-15)/3
z-score = 4/3
z-score = 1.33
The z-score for the monkey is about 1.33
$.75 bc 15 x 4 is 75 so that would make 75¢ or $.75