Answer:
5
Explanation:
4.5*10^-8/ 9*10^-9
1) Reduce the fraction, express 9 as a product of multiplying 4.5*2
4.5*10^-8/4.5*2*10^-9
2) Then notice the common factor of numerator and denominator( 4.5) , get rid of it in both numerator and dnominator
3) 10^-8/ 2*10^-9= 1/2*(10^-8/10^-9)= 0.5* (10^-8/10^-9)
10^-8/10^-9= 10^(-8-(-9))= 10^1=10.
so 0.5*10=5 (it is the answer written in scientific form)