Counting Principle: A student number system for a county requires
that the student number be 4 characters.
The first 3 characters are any single digit number,
and cannot repeat, and the last character must be a
letter. How many unique student numbers are
possible?

a. 260,000
b. 18,720
c. 131,040
d. 315,160

Given: lines a and b are parallel and line c is a transversal. prove: 2 is supplementary to 8 what is the missing reason in the proof? statement reason 1. a || b, is a transv 1. given 2. ∠6 ≅ ∠2 2. ? 3. m∠6 = m∠2 3. def. of congruent 4. ∠6 is supp. to ∠8 4. def. of linear pair 5. ∠2 is supp. to ∠8 5. congruent supplements theorem corresponding angles theorem alternate interior angles theorem vertical angles theorem alternate exterior angles theorem