The difference between an observational study and an experimental is that. A- In an observational study, only one group is studied, and in an experiment , two groups are studied.
B- is an observational study, the researchers do not control treatment , and in an observational study, it is not.
C- in an experiment , cause and effect is analyzed, and in an observational study, it is not.
D- in an experiment, one group is studied over a short period of time, and in an observational study, the group is studied over a longer period of time.

both graphs increase on their domain

neither graph has a y-intercept

step-by-step explanation:

the following points can be visualized easily from the graph

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.

answer: (1,3) (3,-1) (5,-5) ?

step-by-step explanation: