Hello, can someone help me with this?

How does litmus paper indicate an acid?

All of the following are homogeneous mixtures except a) sugar dissolved in water. b) orange juice. c) coffee with cream. d) household vinegar. e) apple juice

Which of the following is an example of how telecommunication devices people do their jobs? a.) a security guard checks the time using a digital watch. b.) a banker does some quick math using a solar calculator. c.) a nurse uses a digital thermometer to take a patient’s temperature. d.) a construction worker reports in to his office using a cell phone.