A supermarket employs 24 shopassistants. 20 of them achieve an average daily turnover of \(\$ 8000\), whereas 4 achieve an average daily turnover of \(\$ 10000\). The corresponding standard deviations are \(\$ 2400\) and \(\$ 3000\), respectively. The daily turnovers of all shopassistants are independent and have a normal distribution. Let \(Z\) be the daily total turnover of all shop-assistants.

(1) Determine \(E(Z)\) and \(\operatorname{Var}(Z)\).

(2) What is the probability that the daily total turnover \(Z\) is greater than \(\$ 190000\) ?