1. what is the fourth term in the expansion of (x + 4y)^6?

a) 7680x^3y^3
b) 3840x^2y^4
c)1440x^2y^4
d)1280x^3y^3

2. a bag contains 6 red marbles, 4 blue marbles, 7 green marbles, and 3 yellow marbles. a marble is drawn from the bag and is not replaced. then a second marble is drawn. what is the probability that both marbles drawn were green?

option a: 49/380
option b: 49/400
option c: 21/190
option d: 21/200

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.

d. 8

step-by-step explanation:

the given radical expression is:

we can rewrite this as:

we express as square numbers to get;

the exponents will now cancel out to give.

the correct answer is d