Answer:
28
Step-by-step explanation:
bc = df x 2
14 x 2 = 28
I hope this helps
Answer: 5, -5
Step-by-step explanation:
There are only 2 square roots of 25: plus and minus 5.

3*boys=2*18
3*boys=36
boys=12
12+18=30
total number of students: 30
Volume of a pyramid = 
Given base is = 140 m
Given height is = 96 m
Volume = 
Hence, volume of pyramid is 4480 m³