The answer would be a. Yes, the student’s answer is
reasonable.
In the problem, it states that Cindy rode her bike for an
hour and ran for an hour. Without the
presence of the comma between rode her bike for an hour, and ran for an hour,
this just means that Cindy only rode her bike and ran it for an hour.
The sentence can be written as Cindy rode her bike and ran
for an hour. So, this gives an answer
that Cindy only exercise for an hour.
Answer:
(c)
"The given statement is true, by definition of length of a vector
,
"
Step-by-step explanation:
(a) 
That is completely correct Remember that if
then

Therefore the correct answer would be (c).
"The given statement is true, by definition of length of a vector
,
"
Its 1/5 likely because my teacher helped me with this problem you welcome:)
Answer: 28.26
Step-by-step explanation:
What your looking for is called the annulus (or the difference of two concentric circles). You can find the annulus by subtracting the area of the inner circle from the area of the outer circle. Volume of a circle= πr²
You are given the diameter in these problems, so you need radius.
For the first circle (8 in one) :
8/2=4 r=4
A=3.14(4)²
A=50.24
For the second one (10 in one) :
10/2=5 r=5
A=3.14(5)²
A=78.5
To find the measure of the annulus, you subtract those numbers, getting 28.26