Complete the notes below. Write NO MORE THAN TWO WORDS for each answer.

游客2024-01-07  20

问题     Complete the notes below.
    Write NO MORE THAN TWO WORDS for each answer.
    Assembly
    Step 1
    Fold  (26)   in half.
    Step 2
    Use  (27)   to secure the ends.
    Step 3
    Attach  (28)   to diver.
    Step 4
    Fill bottle with water and replace  (29)  .
    Step 5
    Demonstrate by squeezing and releasing bottle. Compression causes diver to sink because diver becomes  (30)  .
BOB: Right. Have we got everything now?
JULIA: I think so. I’ve got extras of most things so don’t worry if this doesn’t work first time.
BOB: Okay. Assembly. Step 1.
JULIA: Take a straw and fold it in two. No, not like that—these plastic ones are quite hard to fold—pinchingit in the middle—that should make it easier to bend. You may even have to bite it but not too hard—you want a sharp crease but you don’t want to break it.
BOB: How’s this?
JULIA: Good; now, second step. Wrap a rubber band several times around the ends to hold them together.
BOB: Then?
JULIA: Add weight to the diver.
BOB: So, this straw is the diver?
JULIA: Yes. See how I’m pulling the outside end of a paper clip out a bit? Now, hook the part I bent out intothe rubber band that’s holding the straw together. No, not that way--it’ll fall off. That’s right, turn itover. Now, hook two or three more paper dips on. It’s hard to say how many we’ll need. The idea is toget the diver to be almost all the way submerged, but not quite. We can put it in this tall cup of waterto test it.
BOB: Mum...What do you think? Too buoyant? Add another paper clip?
JULIA: I think so. Okay, onto the next step. Have you got the empty bottle?
BOB: Not quite.
JULIA: What do you mean?
BOB: Well, it’s not quite empty.
JULIA: Pour some into this cup for later. Good. Now fill the bottle with water all the way to the top and we’llgently lower the diver in. Great—now put the cap back on.
BOB: And then?
JULIA: The final step is the demonstration of our experiment—you will see that when I squeeze the bottle, thediver...sinks and when I let it go, the diver...rises.
BOB: When you squeeze, the air bubble trapped in the straw compresses and the water rushes in making itheavier so it sinks. And the reverse happens when you release the bottle. What’s the coat hanger for?
JULIA: Oh, that? If our experiment didn’t work the first time and our diver stayed on the bottom, we’d havehad to fish it out with a piece of wire or a hook of some kind. It’s best to be prepared.

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