What is the significant figure of 378.093

There are 6 sig fig in the number. each digit counts one sig fig, as long as the first digit of a number is not 0. so if it tells you to round off to 1 sig fig, the answer should be 400. 3 is the first sig fig, and you round it up to 4. you cannot write "4" because you have to complete the number to the decimal place.