7friends have a similar cell phone plans. the price of each plan is $x. 3 of 7 friends pay an extra $4 per month for unlimited text messaging write and simplify an expression that represents the total cost of 7 plans

Step-by-step explanation:

7 friends have a similar cell phone plans. The price of each plan is $x. This means that the basic cost of all the plans is $x. The total basic cost for the 7 plans would be

7 × x = $7x

3 of 7 friends pay an extra $4 per month for unlimited text messaging. The total amount paid by the 3 friends would be

3 × 4 = $12

Therefore, the total cost for the 7 plans would be

7x + 12

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.

the correct answer is 5 6 and 7