4. 1st option
5. 2nd option
Answer:
i think its 2 but im not sure
Step-by-step explanation:
sorry if im wrong
Alright, so after a half-life, half of the previous number would be left. So basically,
180 g ← 0 half lives
90 g ← 1 half life
45 g ← 2 half lives
22.5 g ← 3 half lives
11.25 g ← 4 half lives
Therefore, the answer is 11.25 grams
