Alguien me puede ayudar por favor?, Gracias

Electromagnetic induction. a coil of wire contains n turns and has an electrical resistance r. the radius of each turn is a. initially, inside the coil there exists a uniform magnetic field of magnitude b0 parallel to the axis of the coil. the magnetic field is then reduced slowly. the current induced in the coil is i. how long does it take for the magnitude of the uniform field to drop to zero?

If the area of a square has increased by a factor of 16, by how much has each side increased?

What is the largest meteoroid that has collided with this planet