B) a new element is formed
It is the heat required to raise the temperature of the unit mass of a given substance by a given amount (usually one degree).
Explanation:
the table and the wooden block
You didn't mention it, but the trumpeter herself has to be standing still.
<span>Person C, the one running towards the trumpeter, hears a pitch
that is higher than B-flat. (A)
Person B, the one running away from the trumpeter, hears a pitch
that is lower than B-flat.
Person D, the one standing still the whole time, hears the B-flat.</span>