A student researcher conducts an experiment that investigates the effects of a new textbook on student achievement. Two intact classrooms are used for
the samples. One classroom is taught with the new textbook and the other is
taught with the traditional textbook. Each sample consists of 30 students.
Observations of student engagement are rated by the researcher, according
to an engagement scale. How could this study be improved?
Select all that apply.
A. Randomly assign students to two different groups.
B. Administer an instrument, gauging student understanding.
O C. Restrict the study to one group - the one taught with the new
textbook.
D. Have another researcher rate the observations, as well.
SUBMIT

25 questions , because they start with 100.  

350-100=250 .  

. 250/10=25

step-by-step explanation:

first take off 100, then what x 10 = 250? that is your answer. (25)

delaney would like to make a 5lb nut mixture that is 60% peanuts and 40% almonds.

she has several pounds of peanuts and several pounds of a mixture that is 20% peanuts and 80% almonds.

let 'p' represent the number of pounds of peanuts needed to make the new mixture, and  

let 'm' represent the number of pounds of the 80% almond-20% peanut mixture.

:

p + m = 5

therefore

m = (5-p)

write an equation based on the percent of peanuts

1p + .2m = .6(5)

replace m with (5-p)

p + .2(5-p) = .6(5)

p + 1 - .2p = 3

p - .2p = 3 - 1

.8p = 2

p = 2/.8

p = 2.5 lbs of peanuts required

then

5 - 2.5 = 2.5 lbs of the peanut/almond mixture required

:

a) what is the system that models this situation?

p + m = 5

1p + .2m = .6(5)