Your answer is B.
The relationship between medium temperature and speed of sound is a direct relationship: when one factor increases, the other increases as is shown in graph B. The British would choose the the time of day which would give the lowest speed of sound, because this would be easiest to break. Graph B shows that the lowest speed of sound would occur with the lowest air temperature - in the morning.
Answer:
when the water is heated with immersion heater, the water becomes less dense due to which the warm water rises up and the cooler water fills it's space.
osmosis and cellular transport - the physics of molecular movement, kinetic energy and diffusion.
Answer:
d) I and III only.
Explanation:
Let be
and
the masses of the two laboratory carts and let suppose that
. The expressions for each kinetic energy are, respectively:
and
.
After some algebraic manipulation, the following relation is constructed:

Since
, then
. That is to say,
.
The expressions for each linear momentum are, respectively:
and 
Since
, then
. Which proves that statement I is true.
According to the Impulse Theorem, the impulse needed by cart I is greater than impulse needed by cart II, which proves that statement II is false.
According to the Work-Energy Theorem, both carts need the same amount of work to stop them. Which proves that statement III is true.