M = 20.0kg, the mass of the block.
c = 1700 J/(kg-°C), the specific heat
ΔT = 25 - 15 = 10 °C = 10 K, the change in temperature.
The change in thermal energy is

Answer: 340 kJ (or 340,000 J)
How many stairs?
You can use this to find the work
U
W=mgh
And the power by
P=W/T
15 i thank
if u need more help just ask me
Sound source is at rest, you are moving with velocity v, f = frequency, c = speed of sound:
f = f0(1 + v/c)
115 = 100(1 + v/343)
115 = 100 + 100v/343
15 = 100v/343
v = 15*343/100
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v = 51,45 m/s </span>