Concrete placed on a structure was subsequently cored after 28 days and the following results were obtained of the compressive strengths from five test specimens: 3625, 3750, 3825, 3450 and 4155 psi. Part 1) Determine the 90% two-sided confidence intervals of the mean concrete strength. (Answer correct to 1 decimal places) Lower Limit 3568.2 100% Upper Limit 3953.8 100% Part 2) Suppose the confidence interval established is too wide, and the engineer would like to have a confidence interval +310 psi of the computed sample mean concrete strength. What is the confidence level associated with the specified interval based the five measurements given above?

  n=   0.0000 - 0.3750 i  

  n=   0.0000 + 0.3750 i

step-by-step explanation:

one of these should be correct

a net is a diagram that shows a “flattened” view of a solid. in a net, each face and base is shown with all of its dimensions. a net can also serve as a pattern to build a three-dimensional solid.

a pyramid is a three-dimensional object with a base that is a polygon and triangular faces that meet at one vertex.

" the net of a triangular pyramid consists of four triangles. the base here we are given of the pyramid is a equilateral   triangle, and the lateral faces are also triangles "

step-by-step explanation:

f(gx)=f(1/x+2)

=(1/x+2)+2

=(1+2x)/2+2

=(1+2x+4)/2

= (2x+5)/2