There are three significant digits. I am not sure what scientific digits are!
There is no such thing as scientific digits. There are 6 digits in the number of which 3 are SIGNIFICANT (not scientific) digits.
5.4 x 102.
Yes they are, if they are large numbers. You do not need to count how many digits there are.
One digit
In scientific notation that number would be written as 7.080 x 10-3 and it would have four significant digits.
There is no such thing as scientific digits. There are 6 digits in the number of which 3 are SIGNIFICANT (not scientific) digits.
5.4 x 102.
There is no way to know how many significant digits are in 33000. If you are forced to choose then there are 2 significant digits but, again, there is really no way to tell. If the count of significant digits is important, the number should be expressed in scientific notation.
540 what?
Yes they are, if they are large numbers. You do not need to count how many digits there are.
One digit
270 of them.
In scientific notation that number would be written as 7.080 x 10-3 and it would have four significant digits.
The answer depends on what 540 refers to.
540 ÷ 60 = 9
The "fancy" name for fingers and toes is digits.
540 milliliters = 0.54 liters