I already tried to put 4.5 but it didn’t work
Please help

Answer:
4.50 * 10^5
Step-by-step explanation:
We need to notice the 3 significant figures
First change to scientific notation by moving the decimal 5 places to the left. That makes the exponent +5
4.50000* 10^5
We need 3 sig figures
4.50 * 10^5