Given that the premium for a certain insurance is 0.4 ten thousand yuan. For the first 3 claims, each claim pays 0.8 ten thousand yuan; the 4th claim pays 0.6 ten thousand yuan.

\begin{center}
\begin{tabular}{ | c | c | c | c | c | c | }
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Number of Claims & 0 & 1 & 2 & 3 & 4 \\
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Number of Policies & 800 & 100 & 60 & 30 & 10 \\
\hline
\end{tabular}
\end{center}

A sample of 100 policies is drawn from the population. Using frequency to estimate probability:\\
(1) Find the probability that a randomly selected policy has at least 2 claims;\\
(2) (i) Gross profit is the difference between premium and claim amount. Let gross profit be $X$. Estimate the mathematical expectation of $X$;\\
(ii) If policies with no claims have their premium reduced by 4\% in the next insurance period, and policies with claims have their premium increased by 20\%, estimate the mathematical expectation of gross profit for the next insurance period.