One problem facing the manager of maintenance departments is when to change the bulbs in streetlamps. if bulbs are changed only when they burn out, it is quite costly to send crews out to change only one bulb at a time. this method also requires someone to report the problem and, in the meantime, the light is off. if each bulb lasts approximately the same amount of time, they can all be replaced periodically, producing significant cost savings in maintenance. suppose that a financial analysis of the lights at yankee stadium has concluded that it will pay to replace all of the light bulbs at the same time if the variance of the lives of the bulbs is less than . the lengths of life of the last 100 bulbs were recorded. what conclusion can be drawn from these data? use a 5% significance level.

square pyramid

step-by-step explanation:

square prism looks like nothing like that

triangular prism has a rectangular base instead of a square base

tetrahedron has a triangular base

answer: median

step-by-step explanation:

the median is the middle value when a data set is ordered from least to greatest

a triangular prism is a 3 dimensional shape composed of triangles and rectangles. it is made from two triangular bases and three rectangular sides.  

80° is the measure of gh

step-by-step explanation:

circle f is congruent to circle j

we have two circle with center f and j.

both circles are congruent. the radius of the circle would be equal.

see the attachment for the circle.

we are given ∠efd ≅ ∠gjh

therefore, arc (ed) = arc (gh)     (∴ circle f is congruent to circle j)

but ∠dfe=80°=arc (ed)

therefore, arc (gh) = 80°

thus, 80° is the measure of gh