The telephone extensions at a company use 4 digits. a. How many extensions are possible if there are no restrictions?
b. How many extensions are possible if the first digit cannot be 0 or 9?
c. How many extensions are possible if the first digit can only be 1?
Pls help with c

With both problems. a. s.a. p directions on photo ^

(03.03 mc) choose the graph below that correctly represents the equation 2x + 4y = 24. (5 points) select one: a. line through the points 0 comma 6 and 12 comma 0 b. line through the points 0 comma negative 6 and 12 comma 0 c. line through the points 0 comma negative 12 and 6 comma 0 d. line through the points 0 comma 12 and 6 comma 0

Find two numbers if their sum is 91 and the ratio is 6: 7?