Answer:
I think A but I might be wrong good luck
Real number : 8394000000
scientific notation : 8.394 x 10^9
Food handlers who does different cutting surfaces base on cutting raw vegetables and raw poultry, is trying to prevent contamination as doing this prevents food from being mixed and from being contaminated. It is also a way of having the food to be prepared properly and in a more sanitized way for people to eat.
<h2>540 million years ago
</h2>
Paleozoic.
Era immediately follows Precambrian It lasted about 4.5 billion years.
When did abundant fossil evidence first appear in the geologic record.
540 million years ago.