How much time does one person spend on social media in one year

Which of the following is a way the operating system prevents unknown or unauthorized users from accessing the system?

These factors limit the ability to attach files to e-mail messages. location of sender recipient's ability to open file size of file type of operating system used

Which of the following is not a way in which trees benefit the environment? a. they remove a significant amount of carbon dioxide from the atmosphere. b. they remove a significant amount of oxygen from the atmosphere. c. their roots hold soil in place, reducing rates of erosion. d. they remove ozone and particulates from the atmosphere. select the best answer from the choices provided a b c d