ΔCDE was translated down and right to form triangle ΔC′D′E′.

Triangle C E C is translated down and to the right to form triangle C prime D prime E prime.

Which statements are true? Check all that apply.

DE ≅ D′E′
EC ≅ E′C′
ED ≅ D′C′
C′D′ ≅ D′E′
D′C′ ≅ DC
ΔCDE ≅ ΔC′D′E′

1, 2, 5, 6

a) one student is chosen from classroom a, then a student is chosen from classroom b.  

step-by-step explanation:

independent events are ones in which the probability of one event does not affect the probability of the second event.

one student is chosen from classroom a; this does not affect the chances of choosing a student from classroom b.   this makes these independent events.

when one card is chosen from a standard deck and then set aside before a second card is chosen, the probability of the second card being chosen changes.   this makes them dependent events.

when one student is chosen from classroom a and then a second student is chosen from classroom a, the probability of choosing the second student changes.   this makes them dependent events.

when a letter is chosen from the alphabet and then a second letter is chosen, the probability of choosing the second letter changes.   this makes them dependent events.

341

step-by-step explanation:

all you have to do is 9x31 (which equals 279) and then 20x31 (which equals 620). then you have to subtract. 620-279=341.