What are sirens and why does the old man say that there will ALWAYS be sirens

How does the poem's mood and tone change in each of these stages of “o captain! my captain! ” by walt whitman? (i need an answer asap )

You need to start an experiment and the instructions are to mix 2 g of sodium bicarbonate with 50 ml of distilled water and then mix the solution. describe what lab apparatus you would use and what safety precautions you must observe when completing this experiment.

Expand the outline you wrote in lesson 1 about the american dream into an argumentative research essay. as in most essays, you'll need to include an introduction, body, and conclusion. you'll also need to support your claim with evidence