What are differences and similarities between pure substances and mixtures

What prefix multiplier is appropriate for reporting a measurement of 5.57 ×10−5 m?

Wind and moving water provide energy. chemical mechanical thermal none of the above

What is the importance of interlocking the fingers and rubbing while washing hands? the palms are the dirtiest parts of the hands. the spaces between the fingers get washed. the backs of the hands get washed. the fingernails are the dirtiest parts of the hands