(AP STATS...pleasee help me!) At an archaeological site that was an ancient swamp, the bones from 20 brontosaur skeletons have been unearthed. The bones do not show any sign of disease or malformation. It is thought that these animals wandered into a deep area of the swamp and became trapped in the swamp bottom. The 20 left femur bones (thigh bones) were located and 4 of these left femurs are to be randomly selected without replacement for DNA testing to determine gender.
a. Let x be the number out of the 4 selected left femurs that are from males. Based on how these bones were sampled, explain why the probability distribution of Xis not binomial.
b. suppose that the group of 20 brontosaurs whose remains were found int he swamp had been made up of 10 males and 10 females. what is the probability that all 4 in the sample to be tested are male?

Question

(AP STATS...pleasee help me!) At an archaeological site that was an ancient swamp, the bones from 20 brontosaur skeletons have been unearthed. The bones do not show any sign of disease or malformation. It is thought that these animals wandered into a deep area of the swamp and became trapped in the swamp bottom. The 20 left femur bones (thigh bones) were located and 4 of these left femurs are to be randomly selected without replacement for DNA testing to determine gender. 
a. Let x be the number out of the 4 selected left femurs that are from males. Based on how these bones were sampled, explain why the probability distribution of Xis not binomial.
b. suppose that the group of 20 brontosaurs whose remains were found int he swamp had been made up of 10 males and 10 females. what is the probability that all 4 in the sample to be tested are male?