$84 \times (10 + 2) = 84 \times 10 + 84 \times 2 = 840 + 168 = 1008$ 
When Koko the Koala is awake, he eats $84$ grams of leaves per hour. He was awake for $2$ hours yesterday and $10$ hours today. How many grams of leaves did he eat in total in the two days? (adapted from 2014 Math Kangaroo Problem, Level 3-4, Question \#4) 
Options:
A. $$840$$ 
B. $$168$$ 
C. $$672$$ 
D. $$1008$$ 