Leverage and tails

Suppose total initial margin on a Nifty future is 11% of notional (hypothetical). (a) What one-day percentage move in the futures price wipes out the margin of a long? (b) Compute the probability of a fall at least that large on a given day if daily returns are $N(0, 1\%^2)$, and if they follow a Student-$t$ with 3 degrees of freedom scaled to a 1% standard deviation. Convert the second to an expected frequency in years (252 trading days a year). (c) On 23 Mar 2020 the near-month future fell 13.09% in a day. Comment on which model is the better guide to margin adequacy, linking to M02.