You just said that the object is "floating".
(As soon as you said that, a picture of a duck flashed through my mind. But then I knew right away that the duck could not be an accurate representation of the situation you're describing. 340 N would be <u><em>some duck</em></u> ... about 76 pounds ... and that duck would have been caught and eaten a long time ago. I mean ... what could a 76-pound duck do ? Could it fly away ? Could it run away ? ? Not likely.)
So it's not a duck, but whatever it is, it's just sitting there on the water, floating. What's important is that it's <u><em>not accelerating</em></u> up or down. THAT tells us that the vertical forces on it are balanced so that there's NO NET vertical force on it at all.
What are the vertical forces on it ? There's gravity, pulling it DOWN with a force of 340 N, and there's buoyancy, pushing it UP. The SUM of those two forces must be <em>zero</em> ... otherwise the object would be accelerating up or down.
It's not. So (gravity) + (buoyancy) must add up to zero.
The buoyant force on the object is <em>340 N UPward.</em>
Answer:
Part a)

Part B)

Explanation:
Part A)
While escalator is moving up work done to move the person upwards is given as

here we know that
m = 63 kg
h = 4.4 m
now we have


Part B)
Work done while we move from up to down
So we have

so we have

Answer:
No, its not reasonable.
Explanation:
The substance that is to be dissolved is known as solute. The substance that is dissolving is known as solvent.
The amount of solvent in the mixture should be greater than that of solute.
Suppose we are taking a solvent in a beaker and we are continuously adding solute in it. Initially the solute dissolve quickly. At some point the solute stops dissolving in the solvent. This is known as saturation point of the solvent. After saturation point if solute is added further it does not dissolve in the solvent.
So, its not possible to dissolve 12.8 g of one substance in 11 g of another.
It is Continental polar ( only if this is for apex)
The resistance would go down since you essentially have one less resistor