Please answer quick!! Linda randomly surveyed 20 teachers at her school about whether they prefer chalkboards or dry erase boards. She repeated the survey three times with three different sets of teachers.

A 3-column table with 3 rows. Column 1 has entries Sample 1, Sample 2, Sample 3. Column 2 is labeled Chalk with entries 12, 9, 1. Column 3 is labeled Dry Erase with entries 8, 11, 19.

Which pair of Linda’s samples seems to have the lowest variability and, therefore, are representative samples?
A. Samples 1 and 2
B. Samples 1 and 3
C. Samples 2 and 3
D. None of the samples

✔ samples 1 and 2

Step-by-step explanation:

Linda randomly surveyed 20 teachers at her school about whether they prefer chalkboards or dry erase boards. She repeated the survey three times with three different sets of teachers.

A 3-column table with 3 rows. Column 1 has entries Sample 1, Sample 2, Sample 3. Column 2 is labeled Chalk with entries 12, 9, 1. Column 3 is labeled Dry Erase with entries 8, 11, 19.

Which pair of Linda’s samples seems to have the lowest variability and, therefore, are representative samples?

according to egenuity the answer is

step-by-step explanation:

d. 344.22

la parábola es el lugar

geométrico en el cual los puntos tienen una distancia idéntica, equidistantes,

de un punto denominado foco, f, y una recta denominada directriz

el radio vector de una

parábola es el segmento que existe entre un punto cualquiera y el foco.

por la ecuación se observa

que la parábola abre hacia la derecha, por lo cual podemos usar las siguientes fórmulas

la ecuación ordinaria de la

parábola es y^2 = 4px, donde p es la longitud desde el vértice de la parábola al

foco.

la fórmula de la directriz

es x + p = 0

resolviendo:

y^2-9x = 0

y^2 = 9x

4p = 9, entonces p = 9/4

entonces el foco tendrá la

coordenada f(9/4,0)

la directriz vendrá

expresada por

x + p = 0

x = -p

x = -9/4

el problema indica que la

ordenada es igual a 6, entonces

(6)^2=9x

x = 36/9

x = 4

entonces el punto al cual

hay que obtener la distancia será p(4,6)

calculando se tendrá: pf = 

pf = 6,25 u

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step-by-step explanation: