Lorelei evaluates the expression to determine how many different groups of ten she can make out of twelve items. her solution: subtract within parentheses and simplify: expand: divide out common factors: because 6 divided by 2? 1 is 3, there are 3 ways to choose the groups. which statements describe lorelei's solution? check all that apply. her work is correct. her answer is correct. in step 1, the subtraction cannot be completed before the factorial of each number is calculated. in step 1, 12! divided by 10! is not equivalent to 6! divided by 5! . in step 3, the dividing out of common factors was performed incorrectly. there are sixty-six ways to choose ten items from twelve.

Which scenarios are most effectively explored by conducting an experiment? there is more than one correct answer. select all that apply. researchers want to study the effectiveness of a particular drug for treating migraines. they want to know which dosage of the drug yields the best results with the least side effects. to ensure fair results, the researchers want to ensure that participants and dosage administrators do not know which dosage participants receive. a teacher wants to plan a class fieldtrip and quickly determine where students prefer to go for the class fieldtrip. a car mechanic wants to know which of two engine brands makes better-performing engines. he wants to test the engines in identical situations and rate their performance in a way that can be fairly measured. a chemist studies the properties of a metal compound. she wants to know how the sample size of the metal affects its ability to conduct electricity. she wants to conduct the research in a controlled environment to minimize bias. a realty company wants to know the average income of its clients. the company wants to gather data income from current clients.