Identify the type of problem most likely to occur with each of the sampling or experiment methods below: Placebo effect Nonresponse Undercoverage Response bias a) A particular group or groups are left out when collecting a sample from a population. b) A treatment is administered to all members of sample, and the results are observed and measured. c) A sample of people is randomly constructed from a government database and each sample member is mailed a survey and asked to complete and return it. d) A sample of people are contacted by phone and asked about if they have ever performed some illegal activity and if so how frequently.

b

step-by-step explanation:

a difference is the result of subtraction. while each of these expressions has subtraction in it, a difference will be the result when subtraction is the last operation applied in the order of operations for the expression. this means subtraction must be outside of the parenthesis. only b has this.

y=1/4x-4

step-by-step explanation:

d. $180

step-by-step explanation:

if the dimensions of the room is 9ft by 12 ft, we have the area of the floor as,

so the area of the floor is 108 square feet, converting that into square yards we get,

the cost of carpet is $15 per square yard, therefore the cost of carpet for 12 square yards is,

hence, the cost of carpet is $180.

assuming the dimensions of the room be,

15 ft by 12 ft

so, the area of the floor of that room is,

we can convert 180 square feet into square yards, we know that,

1 sq ft = 0.111 sq yard

so, 180 square feet is,

so the area of floor is 20 square yards.

now, the cost of carpet is 15 dollars per square yard, therefore the cost of carpet for 20 square yards is,

so, it will cost $300.

the answer is  

a.

4,624π mm2

step-by-step explanation: