5-3 1/3 a.3 1/3 b.2 2/3 c.2 1/3 d.1 2/3

(hurry! ) which expression is equivalent to the following complex fraction?

Customers at an ice-cream shop took a survey .the results showed that 144 customers rated the shop as being "very satisfactory ."this number represented 45%of the total nunber of customers who took the survey

What is the number 321,000,000 in scientific notation? also what is the number? ?