a)
Check the picture below.
b)
volume wise, we know the smaller pyramid is 1/8 th of the whole pyramid, so the volume of the whole pyramid must be 8/8 th.
Now, if we take off 1/8 th of the volume of whole pyramid, what the whole pyramid is left with is 7/8 th of its total volume, and that 7/8 th is the truncated part, because the 1/8 we chopped off from it, is the volume of the tiny pyramid atop.
Now, what's the ratio of the tiny pyramid to the truncated bottom?

Not sure sorry but you can. Try searching on google or yahoo answers
Answer:
D
Step-by-step explanation:
Call the first person A who can do the job in 5 hours.
Call the second person B who can do the job in 7 hours.
The formula for this problem is
Time = A*B/(A + B)
Time = 5*7 / (5 + 7)
Time = 35 / 12
Time = 2 hours and 11/12 of an hour.
The answer is D.
Answer:
EF ≈ 1.98
Step-by-step explanation:
Using the sine ratio in the right triangle
sin26° =
=
=
( multiply both sides by 4.5 )
4.5 × sin26° = EF
4.5 × 0.44 = EF , that is
EF ≈ 1.98 ( to 2 dec. places )