Answer:
Measuring a pencil in meters would be very difficult, as a single meter is much longer than one pencil. Also, measuring a hallway in millimeters would be very difficult considering how small millimeters are in comparison to a hallway. However, if you switch these two then they would work very well.
Ba2+ and Cu2+, and Sr2+ and Li+
Answer:
C Atomic number
Explanation:
The question is typo it should be 19 is the____ of pottasium. The atomic number is the number on top
