Answer:
20 grams will be left.
Explanation:
Half-life is 11 days
This means that in each 11 days, you lose 50% of the amount.
33 days
33/11 = 3 half-lifes.
You start with 160 grams
After 11 days: 160/2 = 80 grams
After 22 days: 80/2 = 40 grams
After 33 days: 40/2 = 20 grams.
20 grams will be left.