Nucleic acid is the answer for this problem
The word that goes on to the gap is "cells"
Hope it helped!
Answer:
Because the English measurement system has been in use for a very long time, it will be costly and time consuming to change from the English to SI units. Many technological measurements, products, and tools were developed in English units.
The cost of converting all measurements to SI units will be costly and will require a long period of time. Conversions between the English and the SI system of units appear to be more cost-effective than hardware changes.
Example:
It will be costly to convert designs for bridges, tunnels, locomotives, automobiles, and other hardware to the SI system. Although new designs are being performed in SI units, much useful hardware based on English units still remain.
Eventually, it is likely that complete conversion from English to SI units will happen, albeit slowly.
SUBSTANCE: Material composed of only one kind of matter throughout (same atoms or same molecules) ELEMENT: A substance that cannot be decomposed (broken down) into simpler substances by ordinary chemical means. Examples: gold, iron, carbon, hydrogen, oxygen, nitrogen.
