Answer:
The correct answer would be option C.
Step-by-step explanation:
Since he gives the dog 3 liters of water and 500 grams of food a day we know that on the fifth day the dog will have gotten 15 liters of water and 2,500 grams of food.
The half life is 138 days, meaning exactly half of the material will decay after this time. Use this information to find the decay factor 
:
Then after 250 days, there will be
grams left.
Yea since because I have no clue
The expression is no very clear.
It seems to be - x / 7 + 4 < 3x
If so, this is the solution.
1) 3x + x / 7 > 4
2) 21x + x > 28
3) 22x > 28
4) x > 28/22
5) x > 14/11
Answer: x > 14 / 11
