Answer:
Explanation:
Using the below formula
Speed of sound = ( distance between observers) *2/(total time taken)
Now putt the given values ,
time taken = 0.80 sec
distance = 256 m
hence
V of sound= 256*2/0.80
V of sound = 640 m/sec
Answer:
The temperature is 
Explanation:
From the question ewe are told that
The rate of heat transferred is 
The surface area is 
The emissivity of its surface is 
Generally, the rate of heat transfer is mathematically represented as

=> ![T = \sqrt[4]{\frac{P}{e* \sigma } }](https://tex.z-dn.net/?f=T%20%20%3D%20%20%5Csqrt%5B4%5D%7B%5Cfrac%7BP%7D%7Be%2A%20%5Csigma%20%7D%20%7D)
where
is the Boltzmann constant with value 
substituting value
![T = \sqrt[4]{\frac{13.1}{ 0.287* 5.67 *10^{-8} } }](https://tex.z-dn.net/?f=T%20%20%3D%20%20%5Csqrt%5B4%5D%7B%5Cfrac%7B13.1%7D%7B%200.287%2A%205.67%20%2A10%5E%7B-8%7D%20%7D%20%7D)

Tycho Brahe ( 1546 - 1601 ) was a Danish astronomer known for his accurate astronomical and planetary observations. Tycho tried to produce a model with the best of both Ptolemy ( earth-centered solar system ) and Copernicus ( sun-centered solar system ).
Answer: B ) observation.
Answer:
formation of gas bubbles at electrodes
deposition of metals at electrodes
changes in solution colour
electroplating
electrolysis