El núcleo tiene 3 protones (lo que le da al núcleo una carga de +3, identificándolo como el elemento Litio) y 4 neutrones (lo que le da un número total de masa de 7).
Answer:
40N in either direction is the answer
That would be Italian dressing because it does not mix completely therefore it is the definition of a heterogeneous mixture
Answer:
a)
, b) 
Explanation:
a) The magnetic force experimented by a particle has the following vectorial form:

The charge of the electron is equal to
. Then, cross product can be solved by using determinants:

The magnetic force is:

b) The charge of the proton is equal to
. Then, cross product has the following determinant:

The magnetic force is:

Answer:
In D: 3J
Explanation:
Potential energy: Ep=mgh where m is the mass, h altitude.
In point A: h=20cm=0.2m
Epa=12=0.2×mg. Thus mg=12/0.2=60N
For point D: hd=5cm=0.05m
Epd=mg×0.05=60×0.05=3J