Need help with these problems and I have to show my work

Answer:
1. 20 min and 15 sec
2. 4 min and 30 sec
3. y=80x-20
4. the second one
Step-by-step explanation:
1. in 2 min you have 25 g
in 15 sec you loose 2.5 g
2. in 4 min you have 5 g
in 30 sec you loose 5 g
3. y=45x-10
y=80x-20
4. it takes 2 min and 15 sec to empty the first one and 3 min to empty the second one.