3 days they with both have 4 dollars
ANSWER
My answer is in the photo above
EXPLANATION
For all the equations I have used the cross multiplication method although you can also use the LCM method
3x8 is 24 plus 4 is 28
7x1 is 7 plus 2 is 9
9+28 is 37
The relevant rules of exponents are
.. (t^a)^b = t^(a·b)
.. t^a·t^b = t^(a+b)
You have
.. (t^-4)^-9·t^2
.. = t^((-4)*(-9) +2)
.. = t^38 . . . . . . . . . . . selection C