Aresearch group interested in understanding the effect of listening to classical music on leaming mathematics conducted a study. one hundred students were randomly assigned to
one of two groups. the first group listened to classical music as they learned a new lesson. the second group learned the same lesson with no music playing. both groups were tested
on the new material to determine how much they learned. the results for the two groups were compared. what kind of study is this?

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.

b is the correct answer

any of them that add up to 180 degrees.