answer the questions

1. A researcher wants to survey residents of Cebu City regarding their monthly expenditures and decides to interview 39 residents of low-income families, 38 middle-class and 23 well-off residents. What sampling technique is being applied? Random Sampling Systematic Sampling Stratified Sampling Cluster Sampling 2. The average test score of 10 students is 85. What will be the new mean if 1 another student takes the test and scores 20? O 79 O 3. A random variable can be identified as binomial if: There are a fixed number of trials. I1. Each trial only has outcome/'s. III. The outcomes of each trial are independent of one another. IV. The probability of a success remains the same for each trial. O one two three four 4. Suppose the probability that a construction company will be awarded a certain contract is .25, the probability that it will be awarded a second contract is .21, and the probability that it will get both contract is .13. What is the probability that the company will win at least one of the two contracts? O0.30 O 0.33 0.17 0.09