Answer: a) 8.2 * 10^-8 N or 82 nN and b) is repulsive
Explanation: To solve this problem we have to use the Coulomb force for two point charged, it is given by:

Replacing the dat we obtain F=82 nN.
The force is repulsive because the points charged have the same sign.
Answer:
Maximum distance of image from mirror is equal to focal length of the mirror
Explanation:
As we know by the equation of mirror we have

here we know for convex mirror
object position is always negative as it will be placed behind the mirror always
while the focal length of the convex mirror is always taken positive
So here we have


so here maximum value of image distance is equal to focal length of the mirror
<span>The flight controls must be held with left aileron up and elevator neutral while taxiing a tricycle-gear equipped airplane with a left quartering tailwind. In aircraft, ailerons are placed on the trailing edge of each wing near the wingtips and can be moved up and down. So when the left aileron is up, the movement of the airplane moves to the left and turns the wheel in a counterclockwise direction while at the same time, the right aileron is down.
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PHysical properties are properties that do not involve changes in the molecular level. In this case, malleability and magnetism are physical.
Chemical properties involve changes to the substance at the molecular level or change its identity. In this case, reacting with oxygen and nonflammability is a chemical property.