What is the surface area of a square pyramid with a height of 12 mm and a base that measures 8 mm on each side?

266.39mm²

Step-by-step explanation:

The formula for surface area of a square based pyramid =

S.A = a² + 2a √a²/4 + h²

Where

a = base length = 8mm

s = Height of the pyramid = 12mm

Hence,

S.A = 8² + 2 × 8 × √8²/4 + 12²

S.A = 64 + 16 ×√64/4 + 144

S.A = 80 × √16 + 144

S.A = 80 × √160

S.A = 266.39 mm²

Therefore, the surface area of a square pyramid is 266.39 mm²

a² + b²= c²

24² + 7² = c²

c= 25

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.