Under his cell phone plan, Jason pays a flat cost of $60.50 per month and $4 per gigabyte. He wants to keep his bill at $68.90 per month. How many gigabytes of data can he use while staying within his budget?

i believe

step-by-step explanation:

from my conclusion c

the mistake in the pattern is that :

b. the decimal point was moved one too many place values each time

the correct pattern could be made by :

b. moving the decimal point to the right the same numbers of place values as the exponents