2. 
Domain:
, because any value of
is allowed and gives a number
.
Range:
, because
for any positive real
.
y-intercept: This is a point of the form
. So plug in
; we get
. So the intercept is (0, 2), or just 2. (Interestingly, you didn't get marked wrong for that...)
Asymptote: This can be deduced from the range; the asymptote is the line
.
Increasing interval: Going from left to right, there is no interval on which
is increasing, since 1/4 is between 0 and 1.
Decreasing interval: Same as the domain;
is decreasing over the entire real line.
End behavior: The range tells you
, and you know
is decreasing over its entire domain. This means that
as
, and
and
.
3. 
Domain: Same as (2),
.
Range: We can rewrite
.
for all
, so
for all
. Then the range is
.
y-intercept: We have
, so the intercept is (0, -6) (or just -6).
Asymptote: 
Increasing interval: Not increasing anywhere
Decreasing interval: 
End behavior: Similar to (2), but this time
as
and
as
.
Answer:
ceb
Step-by-step explanation:
they're both on the same line (AC) and add up to 180
Answer:
0.36427
Step-by-step explanation:
Mean = λ = 18 messages per hour
P(X = x) = (e^-λ)(λ⁻ˣ)/x!
P(X ≤ x) = Σ (e^-λ)(λ⁻ˣ)/x! (Summation From 0 to x)
But the probability required is that the messages thay come in an hour is between 15 and 20, that is, P(15 < X < 20)
P(15 < X < 20) = P(X < 20) - P(X ≤ 15)
These probabilities will be evaluated using a cumulative frequency calculator.
P(X < 20) = 0.65092
P(X ≤ 15) = poissoncdf(18, 15) = 0.28665
P(15 < X < 20) = P(X < 20) - P(X ≤ 15) = 0.65092 - 0.28665 = 0.36427.
You can use the Poisson distribution calculator here
https://stattrek.com/online-calculator/poisson.aspx