Question: 10 seven samples were taken from an abandoned waste pile...

10. Seven samples were taken from an abandoned waste pile and PCB concentrations of 0.69 mg/kg (s = 0.12 mg/kg). The regulatory soil screening concentration for PCB is 0.74 mg/kg. Using a 90% confidence level, estimate the number of samples required. using the formula n=t^2s^2/e^2