Agraduate student conducted an experiment in which 24 ten-month-old babies were asked to watch a climber character attempt to ascend in hill. on two occasions, the baby witnesses the character fail to make the climb. on the third attempt, the baby witnesses either a toy push the character up the hill or a hinderer toy prevent the character from making the ascent. the 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 21 of the 24 cases, the baby chose the toy.

a. why is it important to randomly expose the baby to the or hinderer toy first?

a. the randomness in the order or exposure is important to avoid bias.

b. the randomness in the order or exposure is important to make sure half the babies see the first and the other half see the hinderer first.

c. the randomness in the order or exposure is important to minimize the effect of the sample standard deviation.

d. the randomness in the order of exposure is important to satisfy the condition of using the binomial probability distribution.

b. what would be the appropriate null and alternative hypotheses if the researcher is attempting to show that babies prefer over hinderes?