1) 4°C : It has the highest density as shown on the graph.
2) Water expands when it freezes, making it less dense than just water.
3) The ice would sink to the bottom, then the rest of the water would freeze as well, the entire lake/river/whatever will freeze eliminating the organisms that live there.
The sun is the primary source of light. Other artificial sources are light bulb, torch light and some others. Thats all i can think of.
Answer:
by lying down on a nice and soft quilted matress
For Science fair project you can do convection current
Explanation:
Show how to do the process
and then make a model to demonstrate
Materials required:
Potassium Permanganate,beaker,bunsen burner,water and retort stand
1. 12.75 J
Assuming that the force applied is parallel to the ramp, so it is parallel to the displacement of the cart, the work done by the force is

where
F = 15 N is the magnitude of the force
d = 85 cm = 0.85 m is the displacement of the cart
Substituting in the formula, we get

2. 10.6 N
In this part, the cart reaches the same vertical height as in part A. This means that the same work has been done (because the work done is equal to the gain in gravitational potential energy of the object: but if the vertical height reached is the same, then the gain in gravitational potential energy is the same, so the work done must be the same).
Therefore, the work done is

However, in this case the displacement is
d = 120 cm = 1.20 m
Therefore, the magnitude of the force in this case is
