Answer:
times it
Step-by-step explanation:
Answer: The tree was 27 feet tall
Step-by-step Explanation: First of all Sally was standing 30 feet away from the tree and she looks up at an angle of elevation of 38 degrees to the top of the tree. With this bit of information we can determine that a right angled triangle has been formed with the reference angle as 38 degrees, the side facing it as h (the height of the tree) and the adjacent side as 30. We shall apply the trigonometric ratio as follows;
Tan 38 = opposite/adjacent
Tan 38 = h/30
0.7813 = h/30
0.7813 x 30 = h
23.4 = h
We remember at this point that Sally’s eyes were 4 feet above the ground. What we have just calculated is the height of the tree from “4 feet above the ground” (where her eyes were). Hence the actual height of the tree is calculated as 23.4 plus 4 which gives us 27.4
Therefore the tree was 27 feet tall (approximately to the nearest foot)
The scientific notation is a method that scientists use
to easily handle very large numbers or very small numbers. As an example,
instead of writing down the value 0.0000000065, we write the value 6.5 x 10-9
in scientific notation. The number of places the decimal point got moved
becomes the exponent of the number 10. When the movement is from left to right,
the exponent is negative (for very small numbers). When it is right to left,
the exponent is positive (for very large numbers).
Therefore writing estimated measurements in scientific
notation:
length of a grain of salt : 0.0002 centimeters = 2 x 10-4
centimeters
width of a key ring : 0.02 centimeters = 2 x 10-2
centimeters
