Fill in the blank with the correct word, phrase or number (no explanations required): (a) Statistical studies can be divided into: where researchers simply observe characteristics and take...

Please answer all 4 with EXPLANATIONS, thank you!

Extracted text: Fill in the blank with the correct word, phrase or number (no explanations required): (a) Statistical studies can be divided into: where researchers simply observe characteristics and take measurements; and where research impose treatments and controls on the subjects, then make observations and measurements. (b) When a random sample taken from a group of 100 people, the probability that any one individual is selected to be in the sample is (c) In Bernouilli trials, there are a fixed number of steps, each resulting in success or failure, and the results of different steps are (d) Two events are independent if the the other event happens. of one event is the same whether or not