Julie finds a snail on the sidewalk and wants to know whether or not the snail moves throughout the day. She places a single mark on the sidewalk next to the snail.
What will Julie use the mark for initially?
determining how fast the snail moves
acting as a standard unit of measure
determining the displacement of the snail
O acting as a reference point for detecting motion

Acting as a reference point for detecting motion

You would be correct, boiling water does disinfect contamination.    the property of disinfecting means to kill  germs, bacteria and other pathogens or contamination  that might cause an infection or cause a person to become sickly. a couple methods of disinfecting are using soap, other cleaning supplies or by simply "boiling" the contaminate.  the reason why boiling water disinfects certain attributes is because some cells cannot survive the heat and pressure.