Pls sm1 help I been asking for help for hours and no answer plss help

Prove that the sum of two consecutive exponents of the number 5 is divisible by 30.if two consecutive exponents are 5n and 5n + 1, then their sum can be written as 30.

Inez has a phone card. the graph shows the number of minutes that remain on her phone card a certain number of days.

Which of the following pair(s) of circles have las a common external tangent? select all that apply. a and b a and c b and c