Answer:
It's the second one. Press 'Ask For Help' if you need more help on problems
Step-by-step explanation:
the electromagnet lasts only as long as there is supply of electric current
1/8 inch thick
inner diameter of 8.5
volume shell=volume total-volume shell
1/8=0.125
diameter/2=radius
radius inner=8.5/2=4.25
radiustotal=inner+outer=4.25+0.125=4.375
so
Vouter-Vinner=(4/3)pi4.375³-(4/3)pi4.25³
Vshell=(4/3)(pi)(4.375³-4.25)
Vshell=(4/3)(pi)(83.740234375-76.765625)
Vshell=(4/3)(pi)(6.974609375)
Vshell=9.299479166666666666666pi cubic inches
Vshell≈16.433536180619 cubic inches
36, 43, 50, 57, 64
36 and 64 are two standard deviations out, so the empirical rule tells us 95% of scores will fall here with a normal distribution
