Neco Model Questions Vol1 2021 Geography Question 17

A chemical plant stores a hazardous material. The probability of an accidental release in a year is \(0.02\). If a release occurs, the expected number of persons affected is given by \(E = k d^{2}\) where \(k = 0.5\) persons km\(^{-2}\) and \(d\) is the distance (km) from the plant to the nearest settlement. The nearest settlement is \(4\) km away. The plant installs a mitigation system that reduces the probability of release by \(30\%\) but increases the effective distance to the settlement by \(20\%\) because of enhanced dispersion. Calculate the new expected annual number of affected persons after mitigation and state whether the annual risk (expected persons) has increased or decreased compared with the original situation.