Answer:
(a) Magnitude: 14.4 N
(b) Away from the +6 µC charge
Explanation:
As the test charge has the same sign, the force that the other charges exert on it will be a repulsive force. The magnitude of each of the forces will be:

K is the Coulomb constant equal to 9*10^9 N*m^2/C^2, q and qtest is the charge of the particles, and r is the distance between the particles.
Let's say that a force that goes toward the +6 µC charge is positive, then:


The magnitude will be:
, away from the +6 µC charge
change in momentum of car is given as

here we have

given that
m = 2000 kg


now we have


The volume corresponds to the measure of the space occupied by a body. From the given dimensions we can intuit that we are looking to find the Volume of an Cuboid, that is, an orthogonal rectangular prism, whose faces form straight dihedral angles.
Mathematically the volume of this body is given as

Where,
L = Length
W = Width
H = High


Note: The value given for the height was in centimeters, so it was transformed to meters.
See the attached image! Thanks!
Answer:
It's H3O+.
Explanation:
The H3O+ ion in the solution is what gives it its acidic properties ( sour taste, low pH , for example). Its known as the hydronium ion.