# The concentration of DDT (C14H9Cl5), in milligrams per liter, is:(1) a nominal variable(2) an ordinal variable(3) an interval variable(4) a ratio variable.

The correct answer is (4) a ratio variable

Step-by-step explanation:

Nominal, ordinal, interval, or ratio data are the four fundamental levels of measurement scales that are used to capture data.

Nominal scales are used for labeling variables, without any quantitative value.

Ordinal the order of the values is what is significant, but the differences between each one is not really known.

Interval we know both, the order and the exact differences between the values

Ratio they have the order, the exact value between units, and have an absolute zero

In this case,  the concentration of DDT (C14H9Cl5), in milligrams per liter is a RATIO,  because it has order, the exact value between units, and have an absolute zero

## Related Questions

Which of the following shows the intersection of the sets? {1, 5, 10, 15} {1, 3, 5, 7}

{ 1,5}

Step-by-step explanation:

The intersection is what the two sets have in common

{1, 5, 10, 15}∩ {1, 3, 5, 7}

= { 1,5}

{1,5}

Step-by-step explanation:

The intersection of the sets are all of the numbers that appear in both sets. In this case, the only numbers that appear in both are 1 and 5.

For any graph of a hyperbola, which of the following statements describes the locations of the foci, vertices, and center with respect to one another ? Select all that apply .A- the foci are closer to the center than vertices

B- the foci are further from the center than the vertices

C- the center is located at the midpoint of the two foci

D- the center is located at the midpoint of the two vertices

A and D because they are both related unlike C and D.

5) if john climbs 30 steps up, then 15 steps down. how many steps did he take?​

Step-by-step explanation:all u have to do is add all that he climbed which is 30+ 15

Step-by-step explanation:

30 + 15 = 45

In a sample of 1200 U.S.â€‹ adults, 191 dine out at a resaurant more than once per week. Two U.S. adults are selected at random from the population of all U.S. adults without replacement. Assuming the sample is representative of all U.S.â€‹ adults, complete partsâ€‹ (a) throughâ€‹ (d). â€‹Required:a. Find the probability that both adults dine out more than once per week. b. Find the probability that neither adult dines out more than once per week. c. Find the probability that at least one of the two adults dines out more than once per week. d. Which of the events can be considered unusual? Explain.

a) The probability that both adults dine out more than once per week = 0.0253

b) The probability that neither adult dines out more than once per week = 0.7069

c) The probability that at least one of the two adults dines out more than once per week = 0.2931

d) Of the three events described, the event that can be considered unusual because of its low probability of occurring, 0.0253 (2.53%), is the event that the two randomly selected adults both dine out more than once per week.

Step-by-step explanation:

In a sample of 1200 U.S. adults, 191 dine out at a restaurant more than once per week.

Assuming this sample.is a random sample and is representative of the proportion of all U.S. adults, the probability of a randomly picked U.S. adult dining out at a restaurant more than once per week = (191/1200) = 0.1591666667 = 0.1592

Now, assuming this probability per person is independent of each other.

Two adults are picked at random from the entire population of U.S. adults, with no replacement, thereby making sure these two are picked at absolute random.

a) The probability that both adults dine out more than once per week.

Probability that adult A dines out more than once per week = P(A) = 0.1592

Probability that adult B dines out more than once per week = P(B) = 0.1592

Probability that adult A and adult B dine out more than once per week = P(A n B)

= P(A) × P(B) (since the probability for each person is independent of the other person)

= 0.1592 × 0.1592

= 0.02534464 = 0.0253 to 4 d.p.

b) The probability that neither adult dines out more than once per week.

Probability that adult A dines out more than once per week = P(A) = 0.1592

Probability that adult A does NOT dine out more than once per week = P(A') = 1 - P(A) = 1 - 0.1592 = 0.8408

Probability that adult B dines out more than once per week = P(B) = 0.1592

Probability that adult B does NOT dine out more than once per week = P(B') = 1 - P(B) = 1 - 0.1592 = 0.8408

Probability that neither adult dines out more than once per week = P(A' n B')

= P(A') × P(B')

= 0.8408 × 0.8408

= 0.70694464 = 0.7069 to 4 d.p.

c) The probability that at least one of the two adults dines out more than once per week.

Probability that adult A dines out more than once per week = P(A) = 0.1592

Probability that adult A does NOT dine out more than once per week = P(A') = 1 - P(A) = 1 - 0.1592 = 0.8408

Probability that adult B dines out more than once per week = P(B) = 0.1592

Probability that adult B does NOT dine out more than once per week = P(B') = 1 - P(B) = 1 - 0.1592 = 0.8408

The probability that at least one of the two adults dines out more than once per week

= P(A n B') + P(A' n B) + P(A n B)

= [P(A) × P(B')] + [P(A') × P(B)] + [P(A) × P(B)]

= (0.1592 × 0.8408) + (0.8408 × 0.1592) + (0.1592 × 0.1592)

= 0.13385536 + 0.13385536 + 0.02534464

= 0.29305536 = 0.2931 to 4 d.p.

d) Which of the events can be considered unusual? Explain.

The event that can be considered as unusual is the event that has very low probabilities of occurring, probabilities of values less than 5% (0.05).

And of the three events described, the event that can be considered unusual because of its low probability of occurring, 0.0253 (2.53%), is the event that the two randomly selected adults both dine out more than once per week.

Hope this Helps!!!

Let P(n) be the statement that a postage of n cents can be formed using just 4-cent and 7-cent stamps. Use strong induction to prove that P(n) is true for all integers greater than or equal to some threshold x.

True for n = 18, 19, 20, 21

Step-by-step explanation:

a postage of cents; where . ( are the number of 4-cent stamps and are the number of 7-cent stamps)

For is true.

This is a possibility, if

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