We have equation:

p = number of phones left to repair
108 = initial amount at the start of week
23 = number of phones repaired each day
d = number of days she worked that week
Answer:
x^12
Step-by-step explanation:
We know that a^b* a^c = a^(b+c)
x^5 * x^7 = x^(5+7) = x^12
Given there is no speed given for the fastest swimming, the tennis ball is 13.07 times f(Fastest Swimming), or 13.07f.