A researcher is interested in estimating the mean weight of a semi tracker tractor truck to determine the potential load capacity. She takes a random sample of 17 trucks and computes a sample mean of 20,000 pounds with sample standard deviation of 1,500. The 95% confidence interval for the population mean weight of a semi tracker tractor truck is .

(19228.737 ; 20771.263)

Step-by-step explanation:

Given that:

Sample size, n = 17

Sample mean, m = 20,000

Sample standard deviation, s = 1500

α = 95%

The confidence interval,

Mean ± margin of error

Margin of Error : Tcritical * s/sqrt(n)

Tcritical at α = 0.05 ; df = n-1 = 17 - 1 = 16 ; 2 - tailed test = 2.120

Margin of Error = 2.120 * 1500/sqrt(17) = 771.263

Lower boundary :

20,000 - 771.263 = 19228.737

Upper boundary :

20,000 + 771.263 = 20771.263

Confidence interval :

(19228.737 ; 20771.263)

answer: b.

step-by-step explanation:

the y coordinate for point b is 0, and answer b is the only one with that y coordinate.

solution:

we have to construct

∠m nt ≅ ∠p qr

the steps to draw this construction are

step 1: use a compass to draw an arc from point q which intersects the side pq at point a and the side qr at point b.

step 2: draw a segment nt and use the same width of the compass to draw an arc from point n which intersects the segment nt at a point x.

step 3:

step 4: join points n and y using a straightedge.

step 3:

option (d).maintaining the same width of the compass as ab, draw an arc from point x such that it intersects the arc drawn from n in a point y.

to draw   congruent angles , 1. width of compasses while drawing two angles should be same i.e from point at which angle has to be drawn, 2.the distance between the two points where the compass intersects the two sides should be same while drawing any two congruent angles.