How many sig figs in 20400?

What number is 13 more than 28? What are consecutive points? Is H2 symmetrical? What comes after theta? What is the symbol for paragraph? Suppose you choose a marble from a bag with 3 red 3 white and 5 blue You return the first marble to the bag and then choose again find P Red then Blue Can anyone help me with this math question? What is the scientific notation of 0.000000034? How are the criulatory resipratory and lympatic system alike? Which type of adverb is too in this proverb? How do you write nine and forty two hundredths? What has three angles two are acute and the other one is right? 14.0067 is round to the nearest whole number? What is 455 in roman numerals? What formula would you use to find out how big an angle is in a stop sign? Is thirty nine prime or composite? What is the empirical method? What is formed by one side of a polygon and a line from the adjacent side? Is there such thing as a 9 digit number? How do you spell 1550? What is one hundred minus one hundred and ten?