Answer:
5
Explanation:
54.34+45.66=100.00 (you have to use the .00 because when you add to numbers you keep the number of decimals)
so you get 100.00
all numbers that are not 0 are sig figs so 1 is a sig fig
If a number ends with a 0 after a decimal place that 0 is a sig fig
all numbers between two sig figs are sig figs so that would make all of the numbers sig figs
