单项选择题 A user states that their web browser was recently updated and continuously crashes. Which of the following could the technician use to gather more information about the issue?（）

单项选择题 Which of the following tools is BEST used to measure voltage and amperage from a power source?（）

单项选择题 A user states that the laser printer is leaving a black line on all pages being printed. Which of thefollowing is the MOST likely cause and solution for this issue?（）