Which graph represents a function with a growth factor of 5

Bismuth-210 is an isotope that radioactively decays by about 13% each day, meaning 13% of the remaining bismuth-210 transforms into another atom (polonium-210 in this case) each day. if you begin with 233 mg of bismuth-210, how much remains after 8 days?

What is the slope of the line shown below?

Corresponding angles are a. always b. sometimes c. never congruent