Help e cause I'm stuck

3^15

Step-by-step explanation:

3^5 means 3*3*3*3*3

3^10 means 3*3*3*3*3*3*3*3*3*3

so 3^5 * 3^10 means  3*3*3*3*3 * 3*3*3*3*3*3*3*3*3*3 = 3^15

The rule is that you can add the exponents if the base number (3) is the same.

i dont know

step-by-step explanation:

umm. i dont know

x= cost per bracelet

number of bracelets * x + shipping charge = total cost

so

9x+9=72