Answer:
Option C, increases and decreases
Explanation:
When an object making noise approaches you, the wave frequency increases leading to a higher pitch. Conversely, when it moves away from you or retreats, the wave frequency decreases leading to a lower pitch. This can be observed in ambulance sirens.
d
a has a faster period
Period only depends on the length, irrelevant to the mass.
a has a shorter length, so has a small period, or faster.
204 kJ
Heat energy can be calculated using
Q=mcθ
where Q = Heat energy
m =mass
c = specific heat capacity
θ =temperature difference
Q = 12 * 1700*10
= 204000 J
= 204 kJ
These are the correct answers. I couldn't get the rest of the answers