A student uses external standard calibration to calculate the concentration of caffeine in beverages. The calibration curve equation is found to be y = 1.012x + 0.671, where the calibration standards are in units of mg/mL. A student runs a beverage sample and gets a response of 7.018. The concentration of caffeine in this beverage is:
6.929 mg/mL
None of These
10.46 mg/mL
0.663 mg/mL
6.272 mg/mL