What is the exponent on 10 when you write 5.3 in scientific notation

Nick has box brads. he uses 4 brads for the first project. nick let’s b represent the original number of brads and finds that for the second project, the number of brads he uses is 8 more than half the difference of b and 4. write an expression to represent the number of brads he uses for the second project.

Icould really use some with this question.

Apackage of orgainc strwberries costs $1.50 while there in season and $2.25 when not in season what the percent increase