Do people walk faster in the airport when they are departing (getting on a plane) or do they walk faster when they are arriving (getting off a plane)? A reputable researcher measured the walking speed of random travelers in two International Airports. His findings are summarized in the table. Complete parts (a)-(c) below.

Direction of travel Departure Arrival

mean speed(feet per minute) 254 268

standard deviation(feet per minute) 53 34

Sample size 35 35

a) Is this an observational study or a designed experiment? Why?

A. This is an observational study since the researcher influenced the data

B. This is a designed experiment since the researcher influenced the data

C. This is a designed experiment since the researcher did not influence the data

D. This is an observational study since the researcher did not influence the study

b) Explain why it is reasonable to use Welch's t-test.

A. The samples are random, large and dependent

B. The samples are random, large and independent

C. The samples are random, small and independent

D. The populations are normally distributed

(c) Do individuals walk at different speeds depending on whether they are departing or arriving at the a=0.01 level of significance? Let 1represent the mean speed of people departing and 2 represent the mean speed of people arriving.

A. H0:1=2 B. H0:1<2 c. h0:1=2 d.>

H1:1 2 H1:1 > 2 H1:1 < 2 H1:1> 2

Determine the P-value for this hypothesis test.

p value=_________(Round to three decimal places as needed.)

Choose the correct conclusion.

A. Do not reject H0; there is not sufficient evidence at the a=0.1 level of significance to say that the travelers walk at different speeds depending on whether they are departing or

arriving

B. Do not reject Ho; There is sufficient evidence at the a=0.1 level of significance to say that the travelers walk at different speeds depending on whether they are departing or

arriving

C. Reject H0; there is sufficient evidence at the a=0.1 level of significance to say that the travelers walk at different speeds depending on whether they are departing or

arriving

D. Reject H0; there is not sufficient evidence at the a=0.1 level of significance to say that the travelers walk at different speeds depending on whether they are departing or

arriving