Given: ABCD is a square. Put a checkmark in every box that must be
true. You will put more than one checkmark.
Has two pairs of parallel sides
Has exactly one pair of parallel sides
All four sides are congruent
Has exactly one pair of congruent sides
Both pairs of opposite sides are congruent
Two pairs of consecutive sides
(but not all four sides) are congruent
There are right angles at all four vertices
The diagonals are perpendicular
The diagonals are congruent
The diagonals bisect each other

The answers are:

Has two pairs of parallel sides

All four sides are congruent

Both pairs of opposite sides are congruent

There are right angles at all four vertices

The diagonals are perpendicular

The diagonals are congruent

The diagonals bisect each other

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.