Karri tests the charges of a random sample of 64 batteries from a large production run. The mean charge was 8.93 volts, and the process typically has a standard deviation of 0.2 volts. To see if the batch has a significantly different mean voltage from 9 volts, the value of the z-test statistic would be .

The Z-statistic value is

                  Z = -2.33

Step-by-step explanation:

Step(i):-

Random sample size     'n' = 64

mean of the sample  'x⁻ ' = 8.93 volts

standard deviation of the sample  = 0.2 volts

mean of the Population"μ" = 9 volts

Step(ii):-

Z -statistic

Conclusion:-

The Z-statistic value is  = -2.33

b. an equilateral triangle inscribed in a circle

step-by-step explanation:

we are given the figure of two circles having a triangle inside.

now, we know that,

"when a figure is lying inside an another figure, then the outside figure is known as circumscribed figure and the figure lying inside is referred to as the inscribed figure".

as we see that, the circles are containing the triangle completely.

thus, the circles are the circumscribed figures and the triangle is the inscribed figure.

hence, we get, 'an equilateral triangle is inscribed in a circle'.

a and c

step-by-step explanation: