Answer:
Step-by-step explanation:
<u>Equation</u>:
- cos x = 15/21
- cos x = 0.714
- x = arccos 0.714
- x = 44° (rounded to the nearest degree)
Scientific notation is a way of writing numbers in a form of a decimal multiplied by an exponent of 10.
For these, the exponent will be negative, since they're teeny tiny decimals, and we'll have to move the decimal point back to the right.
0.00000012 will become
This is because the decimal point is moved seven places to the right of where it originally was.
0.000005008 will become

Again, this is because the decimal point is moved seven places to the right of where it originally was.
So, your scientific notations are

and
The radius of the water bottle to the nearest hundredth is 2.01 cm
<h3>How to calculate the volume of a cylinder</h3>
A cylinder is a solid figure with circular bases and height.
The volume of a cylinder = πr²h
h is the height = 8.1cm
Volume = 103 cubic cm
Substitute into the formula to have
V = 3.14r² * 8.1
103 = 3.144 * 8.1 * r²
r = 2.01 cm
Hence the radius of the water bottle to the nearest hundredth is 2.01 cm
Learn more on volume of cylinder here: brainly.com/question/9554871
Answer
speed : metres per second (a)
perimeter : meters (b)
volume : cubic centimetres (d)
area : square metres (c)