The answer is 3 (or 3.08)
Answer: B. 

Step-by-step explanation:
Let
be the proportion of all U.S. adults that smoked in 1995. Let
denote the proportion of all U.S. adults that smoked in 2000.
Objective for the study : Whether the proportion of U.S. adults that smoke declined during the 5-year period between the samples.
i.e. 
Alternative hypothesis
is the statement containing population parameter that shows there is significant difference between the groups being tested.
⇒ 
Null hypothesis
is the statement containing population parameter that shows there is no significant difference between the groups being tested.
⇒ 
Hence, The hypotheses to test in this problem are


Hence, the correct answer is B. 

Equation of a tangent line of a curve is:
y- y0 = f´ (x0) (x - x0 ). In this case: x0=1, y0=1
f´(x)=

(Derivation)
f´(x0)=

y - 1 = 1/2 ( x - 1 )
y - 1 = 1/2 x - 1/2
y = 1/2 x - 1/2 + 1
y =
Changing the h value will move the graph horizontally left or right.
Answer:
3rd one: 
Step-by-step explanation: