Science help plzz?

A man decides to build a boat. In order to make it durable, he decides to use solid steel. When he brings his boat to the lake, it sinks straight to the bottom. What could the man do to help make a boat that floats?
A)
He will never be able to use steel to make his boat.
B)
Add more steel to the sides of the boat

A man decides to build a boat. In order to make it durable, he decides to use solid steel. When he brings his boat to the lake, it sinks straight to the bottom. What could the man do to help make a boat that floats?
A)
He will never be able to use steel to make his boat.
B)
Add more steel to the sides of the boat to help it balance.
C)
Make the boat smaller, but continue to use the solid steel.
D)
Create a hollow area inside the steel to help lower the boats density.

Other answer:

Niquee Jenkins:
D is the answer they're looking for, however… it is incorrectly stated.

In the same manner, Sailor's correction is partially right but inaccurate. It is not to lower the weight of the boat.
It's to increase the volume of water displaced by the boat.

Buoyancy is the force acting upwards on a floating or submerged object by the surrounding fluid(water, air) displaced by the object.

Whether that object sinks or floats depends on the relationship between the weight of the object and the weight of the fluid displaced.
If a material is denser than water, yet it's shape displaces a volume of water that is greater in weight than that of the object. it will be positively buoyed and will rise up and float.

As a submerged object reaches the surface, the part above water no long displaces water. The volume of water displaced shrinks and consequently, so too does the total weight of the displaced water. When the weight of displaced water exactly equals the total weight of the object, that it is point at which it floats, no longer rising out of the water, no longer sinking into the water.

Sailor:
D is partly the correct answer. It is however not the decrease in the boats density as the density of an object does not change.. What you are doing is decreasing the weight of the object up to the point where it will displace a volume of liquid whose weight is equal to its own. At this point the boat will float, as per Archimedes principle.
Answer B will also have a similar result if by doing so the added steel is all around the boat.
Eric West:
Boats float because they displace the same amount of water as the weight of boat immersed in the water. So what you need is a boat which displaces a lot of water for its weight, then more will be above the surface.

You can do that by making the boat wider or deeper, so that more boat is submerged before water flows in.

Work out which is the best answer considering that

Percyqted:
D

All modern ocean going ships are made of steel. He needs to make the sides high enough (create hollow space) to allow for the displacement weight of the steel

?:
A
Girly Brains:
D.

"Create a hollow area inside the steel to help lower the boat's [average] density."
______________

Edit: Add media:-

Example:

Create a hollow to reduce average density of ship from 8t/m³ (more dense than water) to ½t/m³ (less dense than water):

1 cubic metre is the volume of the WHOLE ship (in both cases).

8 tonnes (solid) and ½ tonne (hollow) are the weights of the WHOLE ship (in both cases).

½ a tonne per cubic metre is a LOWER density than 8 tonnes per cubic metre.
______________

An 8 tonne ship with total volume 1m³ displaces 1m³ of water (and sinks).

A ½ tonne ship with total volume 1m³ displaces ½m³ of water (and floats – safely)!

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