A graduate student conducted an experiment in which 22 22ten-month-old babies were asked to watch a climber character attempt to ascend a hill. On two occasions, the baby witnesses the character fail to make the climb. On the third attempt, the baby witnesses either a helper toy push the character up the hill or a hinderer toy prevent the character from making the ascent. 

The helper and hinderer toys were shown to each baby in a random fashion for a fixed amount of time. The baby was then placed in front of each toy and allowed to choose which toy he or she wished to play with. In 20 20 of the 22 22 cases, the baby chose the helper toy. Complete parts (a) through (d) below. (a) Why is it important to randomly expose the baby to the helper or hinderer toy first? 

A. The randomness in the order of exposure is important to satisfy the conditions of using the binomial probability distribution. 

B. The randomness in the order of exposure is important to avoid bias. 

C. The randomness in the order of exposure is important to minimize the effect of the sample standard deviation. 

D. The randomness in the order of exposure is important to make sure half the babies see the helper first and the other half see the hinderer first. 

(b) What would be the appropriate null and alternative hypotheses if the researcher is attempting to show that babies prefer helpers over hinderers? Upper H 0 H0: p ▼ equals = less than < not equals ≠ greater than > 0.5 Upper H 1 H1: p ▼ equals = greater than > not equals ≠ less than < 0.5 

(c) Use the binomial probability formula to determine the P-value for this test. P-value equals = nothing(Round to three decimal places as needed.) What is the correct conclusion regarding the null hypothesis?

 A. Do not reject Upper H 0 H0. Although no level of significance is given, there is sufficient evidence to suggest the proportion of babies who choose the helper toy is greater than 0.5. B. Reject Upper H 0 H0. Although no level of significance is given, there is sufficient evidence to suggest the proportion of babies who choose the helper toy is greater than 0.5. 

C. Reject Upper H 0 H0. Although no level of significance is given, there is insufficient evidence to suggest the proportion of babies who choose the helper toy is greater than 0.5. 

D. Do not reject Upper H 0 H0. Although no level of significance is given, there is insufficient evidence to suggest the proportion of babies who choose the helper toy is greater than 0.5. 

(d) In testing 12 12 six-month-old babies, all 12 12 preferred the helper toy. The P-value was reported as 0.0002 0.0002. Interpret this result. Choose the correct answer below. 

A. If the population proportion of babies who choose the helper is0.5, a sample where all 12 12 babies choose the helper will occur in exactly 2 2 out of 10,000 samples of 12 12 babies. 

B. If the population proportion of babies who choose the helper is 0.5, a sample where all 12 12 babies choose the helper will occur in exactly 12 12 out of 1000 samples of 12 12 babies. 

C. If the population proportion of babies who choose the helper is 0.5, a sample where all 12 12 babies choose the helper will occur in about 2 2 out of 10,000 samples of 12 12 babies. 

D. If the population proportion of babies who choose the helper is 0.5, a sample where all 12 12 babies choose the helper will occur in about 12 12 out of 1000 samples of 12 12 babies.

Answer rating: 100% (QA)

As given in the question The total number of cases n 21 The number of times the baby chose the helpe... View the full answer