Answer: (D) The external validity of the study
Explanation:
The external validity is the type of study which basically depicts that the concept of the study result must be meaningful. The external validity mainly apply in the conclusion in the scientific concepts and study about the main context.
External validity is the type of validity in which we extent the result of the study across the different types of situations, times and people. In mathematics, the external validity concept is applicable for determining the statistical and the various computational methods.
Answer:
d. 
Step-by-step explanation:
We have been given that Cheng measures each edge of each base to be 2 feet. The height of the whole sculpture is 6 feet.
First of all, we will find height of each pyramid by dividing height of whole sculpture by 4 as:

We know that volume of a pyramid is equal to 1/3 of base area times height that is
, where b represents area of base.

Since volume of one pyramid is equal to 2 cubic feet, so volume of 4 pyramids will be 4 times 2 cubic feet that is 8 cubic feet.
Therefore, Cheng must purchase 8 cubic feet of material.
Answer:
X=7.9
Y=7.9
Step-by-step explanation:
We have that x=y
And form Pythagoras theorem we have

So x = y = 7.9
If 2 inches equals 40 miles, then 1 inch equals 20 miles.
115 miles/20 miles=5.75
The cities would be 5.75 miles apart on the map.
14.14 cuz that’s the equation for diameter to circumference