Answer ; The correct answer is : 346 m/s .
Sound is a type of longitudinal wave , which is produced when a matter compress or refracts .
Speed of sounds depends on factors like medium , density , temperature etc .
Effect of Temperature on speed of sounds :
When the temperature increases , molecules gains energy and they starts vibrating and with higher temperature vibration becomes fast . So the waves of sounds can travel faster due to faster vibrations . Hence , speed of sounds is directly proportional to the temperature or speed of sounds increases with increase in temperature .
The speed of sounds at 0⁰C is 331 
The relation between speed of sound and temperature is given as :

Given : Temperature = 25 ⁰ C
Plugging values in formula =>



I'm not sure but i would say C.storing the heat energy.
2 H₂O₂ --> 2 H₂ + 2 O₂
2 moles H₂O₂ ------> 2 moles O₂
8 moles H₂O₂ ------> ?
moles O₂ = 8 x 2 / 2
moles O₂ = 16 / 2
= 8 moles
Answer C
hope this helps!
Force = mass x gravity
Force = 20 kg x 9.8 m/s²
Force = 196 Newtons
Answer A
hope this helps!