Hi!
Our sky is blue because air molecules will span out <em>blue </em>light from our sun more than <em>red </em>light from our sun.
If you look at the sun, you'll see orange and red colours due to the fact that the suns blue light has already been disbursed away from our line of sight.
Hopefully, this helps! =)
The value of A is 78 degrees.
The freshet is basically a flood that occurs because of heavy rainfall or because of the melting of a snow.
This type of flooding is most common in the valleys of the larger rivers, especially the ones that start their flow high in the mountains.
The large rivers have much more water, and they also have lot of tributaries, so when there's a heavy rainfall they receive enormous amounts of water, which easily causes a flood.
Also, when the snow melts, lot of water is released from it, and most of that water gets into the river, or first in its tributaries and that in it, so there's a high possibility of a big flood occurring suddenly.