A water pipe freezes and cracks on a cold night. <em> (D)</em>
There are three physical changes going on in this scenario:
1). The air gets cold and dark at night.
2). The water in the pipe freezes and expands.
3). The pipe cracks.
There are no chemical changes in the description.
Answer:
8977.7 kg/m^3
Explanation:
Volume of water displaced = 55 cm^3 = 55 x 10^-6 m^3
Reading of balance when block is immersed in water = 4.3 N
According to the Archimedes principle, when a body is immersed n a liquid partly or wholly, then there is a loss in the weight of body which is called upthrust or buoyant force. this buoyant force is equal to the weight of liquid displaced by the body.
Buoyant force = weight of the water displaced by the block
Buoyant force = Volume of water displaced x density of water x g
= 55 x 10^-6 x 1000 x .8 = 0.539 N
True weight of the body = Weight of body in water + buoyant force
m g = 4.3 + 0.539 = 4.839
m = 0.4937 kg
Density of block = mass of block / volume of block
= 
Density of block = 8977.7 kg/m^3
If he's going back using the same roads, then he would have to drive 4km west and then 3km north. If he wants to go diagonally straight to the point of his beginning, then you apply the Pythagorean theorem. c2 = a2 + b2 - the 2 means squared
c2 = 4squared + 3squared
c2 = 16 + 9
c2 = 25
c = SquareRoot of 25
C = 5
If he goes diagonally, then he needs to travel 5km.
Conductors, or metals. Like copper wires, scissors, and the exception of non-metal water, too.