1) Which statement contains an exact number? A) A gross of paper contains 144 sheets. B) One sheet of paper is 0.0042 inches thick. C) One sheet of paper measures 8.5 x 11 inches. D) A ream of medium weight paper weighs 20 pounds. A

B) One sheet of paper is 0.0042 inches thick

Step-by-step explanation:

All the other values are not give from just a sheet of paper, and/or they are either a cumulative value, or values that will be used to calculate another value

Only option B defines a value for a unit of paper, and the value is definite.

Option A indicates  the number in a group (gross)

Option C shows two values that can be used to calculate one value; the area.

Option D indicates an accumulated value of weight.

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.

14.29%

step-by-step explanation: