The difference between an observational study and an experiment is that.

A in an experiment, cause-and-effect is analyzed, and in an observational study, it is not.

B 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.

C in an observational study, only one group is studied, and in an experiment, two groups are studied.

D in an observational study, the researchers do not control treatment, and in an experiment, they do.

Its:

in an observational study, the researchers do not control treatment, and in an experiment, they do.

Step-by-step explanation:

It was D for you, but B for e :)

f(x) = - 2/3x + 5; f(5/2)

substitute 5/2 in for x:

f(5/2) = -2/3(5/2) + 5

simplify the right side:

f(5/2) = -5/3 + 5

f(5/2) = 10/3

answer:

f(5/2) = 10/3

i hope this you!

answer: c, the green line

step-by-step explanation:

there is no black line, eliminate b.

simple interest implies periodic payments, but the red line shows no payments, eliminate d.

simple interest has equal payments. if paid say every day, the graph is about a straight line (actually a stairstep).

the yellow line is not straight, eliminate a.

check: the green line is straight, answer is c.

simple interest with positive interest rate gives a straight line sloping up to the right. green line:

g(t) = $100 + ($200-$100) ÷ (20 years) × (t years)

= $100 + (4%/year) × ($100)(t years)

incidentally, the yellow line curving upward represents continuously compounded interest

y = $100 × 2^(t years / (14 assuming the yellow line hits $200 at 14 years. 2^0 is 1, so y(0) = $100; 2^(14/14) is 2, so y(14) = $200.