Explanation:
This problem can be solved by using the formula

where m is the mass of the ion, v is the velocity, q is the charge, B is the strength of the magnetic field and r is the radius of the circular motion of the ion.
(a) Taking q from the equation and by replacing we have
.
(b)
≈ 3*10^(10) C
the ion has 2.99*10^(10) more charge than an electron .
(c) The ratio must be an integer because the electrons are indivisible.
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