Answer: it's B because i tried C, and A, and i know it's not D
i hope this helped you
Find the area of the parallelogram with vertices A(−1,2,3), B(0,4,6), C(1,1,2), and D(2,3,5).
cupoosta [38]
Answer:
5*sqrt3
Step-by-step explanation:
The vector AB= (0-(-1), 4-2,6-3) AB= (1,2,3)
The modul of AB is sqrt(1^2+2^2+3^2)= sqrt14
The vector AC is (1-(-1), 1-2, 2-3)= (2,-1,-1)
The modul of B is sqrt (2^2+(-1)^2+(-1)^2)= sqrt6
AB*AC= modul AB*modul AC*cosA
cosA=( 1*2+2*(-1)+3*(-1))/ sqrt14*sqrt6= -3/sqrt84=
sinB= sqrt (1- (-3/sqrt84)^2)= sqrt75/84= sqrt 25/28= 5/sqrt28
s= modul AB*modul AC*sinA= sqrt14*sqrt6* 5/ sqrt28= 5*sqrt3
The correct answer is B. Stratified sampling is used since the field is divided into subplots and a random sample is taken from each subplot.
Explanation:
Sampling refers to the process followed by researchers to select a group of individuals from a larger group; considering in most studies it is not possible to analyze all the population. In the case of stratified sampling, this involves dividing the general population into smaller groups, which are known as strata; after this, the researcher selects a specific number of individuals from each strata. This method guarantees the sample is selected randomly, and therefore the study is not biased. Stratified sampling was the method used in the example described because, in this, the general population (46-acre field) was divided into subplots that represent the strata. Also, after this, the researcher selected one random sample.
19/30 20/30 21/30 22/30 23/20
Solve it like a normal equation, but with < instead of =
9k - 2 < 3k + 10
-3k -3k
_____________
6k - 2 < 10
+2 < +2
_____________
6k < 12
÷6 ÷6
_____________
k < 2 is your final answer :)
