What does below science rebus mean?

Ag Ag Ag
Ag SPOON Ag
Ag Ag Ag

I have cities, but no houses. I have mountains, but no trees. I have water, but no fish. What am I?

When is the top of a mountain similar to a savings account?

2, 3, 5, 9, 17, _ What is the next number in the sequence?

Do you know of a place where the wind blows south and then suddenly shifts direction towards the north?

What month of the year has 28 days?

What does this rebus picture identify?

Speaking of rivers, a man calls his dog from the opposite side of the river. The dog crosses the river without getting wet, and without using a bridge or boat. How?

John speaks the truth only once a day in a week. Below are a few hints for you:

First: Days are Sunday, Monday and so on.
Second: One day he says, "I lie on Monday and Tuesday".
Third: On the next day, he says, "Today is either Thursday, Saturday or Sunday".
Fourth: On the next day, he says, "I lie on Wednesday and Friday".

Can you identify the day on which he speaks the truth?

What does this rebus means ?