You measure the mass of a book and it’s 420.0890g how many significant digits are in the measurement

9514 1404 393

  7

Step-by-step explanation:

All of the digits in the given number are significant. There are 7 significant digits.

__

Comment on other cases

When there are non-zero digits to the left of the decimal point in a number with a decimal point, all of the digits are significant.

When there are no non-zero digits to the left of the decimal point, leading zeros are not significant. All digits following the leading zeros are significant.

In a number with no decimal point, the leading and trailing zeros are not significant.

If the number is written in scientific notation, all digits of the mantissa are significant. (This can be a way to ensure the correct number of significant digits is known in a number with trailing zeros.)

im not sure

step-by-step explanation:

so far i think you have the right thing going for you just remember soh cah toh

step-by-step explanation:

sine over hypotenuse

cosine   equals adjacent

tangent over hypotenuse