Problem #3: A sample of naturally occurring radioactive material of is decaying exponentially, with an initial amount of 630 [4 marks] units. After 5 years, the amount of radioactive material has decreased to 210 units. (a) How many units of radioactive material will there be after 10 years? (b) What is the half-life of the radioactive material (in years)? Problem #3(a): (A) TO (B) (C) In 2 In 2 5 In 2 15 (D) 2 (E 5 In 3 (F) In 3 Problem #3(b): Select v T Part (b) choices. Save Your work has been saved!_(Back to Admin Page). Problem #4: Consider the following graphs [4 marks] (1) (2) 0.5- -271 -1.57 An -0.5% 0.5TT 17 1.57 2 7 -0.5