GIVING BRAINLIEST HELP ASAP Keith purchased a prepaid phone card for $15.00 . Calls cost 9 cents a minute using this card. The credit, C (in dollars), left on the card after it is used for x minutes of calls is given by the following function.

C(x)=$15.00-0.09x

How much credit is left on the card after Keith uses it for 30 minutes of calls?

2 dollars and 70 cents

Step-by-step explanation: i hope dis helped

b. 6

step-by-step explanation:

we are given the table representing an exponential function.

we can see from the table that, as x is increasing, the value of y is increasing in the power of 6.

i.e. the following relation is obtained,

x = 1, y = 6

x = 2, y = 36 =

x = 3, y = 216 =

x = 4, y = 1296 =

x = 5, y = 7776 =

so, the geometric series obtained is .

thus, the common ratio is given by = = 6.

hence, the common ratio is 6.