Answer:
I think it's A but I'm not sure
In a cup of water it is a positive and negative charge of zero
Answer:
a. -5,4
b. 28
Explanation:
(see how to solve in pic)
Answer:

Explanation:
At thermal equilibrium we have heat given by aluminium must be equal to the heat absorbed by the water
so we will have


so we will have

so we have

so we have


Explanation:
∆x=300 m×2
∆t=1.5 s
v=∆x/∆t → v=2×300/1.5 = 400 m/s