The mass of the water with the sugar dissolved in it is 55 grams. This is because when you add the weight of the water, and the sugar that you added, it is 55.
<h3>answer</h3>
The minimum velocity required for a object to rotate in a verticle plane is v
1
=
5
gr.
So, at bottom point, T
max
=mv
1
2
/r+mg=6mg.
At top-most point velocity is v
2
=gr.
So, T
min
=mv
2
2
/r−mg=0
So T
max
−T
min
=6mg=2×g⇒m=1/3 kg
Not totally sure but i would say a normal? its not refraction or incidence if its perpendicular and i dont think its a mirror if its an imaginary line so yeah normal (normals are always perpendicular to their surface too i think so)