Let x be the set of the 26 lowercase english letters and 10 decimal digits. how many x-strings of length 15 satisfy all of the following properties (at the same time)?

a. the first and last symbols of the string are distinct digits (which may appear elsewhere in the string).
b. precisely four of the symbols in the string are the letter ’t’.
c. precisely three characters in the string are elements of the set v fa; e; i; o; ug and these characters are all distinct.

c is the correct answer

step-by-step explanation:

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.

is there a picture

step-by-step explanation: