First of all, this is not an observational study, but an experiment, since we have two groups and one of the two groups is manipulated or treated. In an observational study the subjects are only observed.
Second, the students did not choose their groups - so we can't choose the last answer.
Therefore the correct answer is:
This is an experiment because a treatment was applied to a group.
Answer:
To get the reciprocal of a fraction, just turn it upside down. Like this: 3. 4. A Fraction ... Convert it to an improper fraction: 213 = 6 3 + 1 3 = 7 3 2.
Step-by-step explanation:
Answer:
In Exercises 1-15 use mathematical induction to establish the formula for n ≥ 1.
1. 1
2 + 22 + 32 + · · · + n
2 =
n(n + 1)(2n + 1)
6
Proof:
For n = 1, the statement reduces to 12 =
1 · 2 · 3
6
and is obviously true.
Assuming the statement is true for n = k:
1
2 + 22 + 32 + · · · + k
2 =
k(k + 1)(2k + 1)
6
, (1)
we will prove that the statement must be true for n = k + 1:
1
2 + 22 + 32 + · · · + (k + 1)2 =
(k + 1)(k + 2)(2k + 3)
6
. (2)
The left-hand side of (2) can be written as
1
2 + 22 + 32 + · · · + k
2 + (k + 1)2
.
In view of (1), this simplifies to:
Answer:
a= 3 b=6 c= 5
Step-by-step explanation:
Point slope uses one point and the slope. We’ll use (4,10)
Y - 10 = 2 • (x - 4)
But it can also be
Y - 4 = 2 • (x - 1)
Whichever you prefer to use