From a lighthouse L two ships P and Q are observed south west and 5°east of South respectively. At the same time Q is observed from P in South East direction. If LP=4km, the distance between the ships is ________
From a lighthouse L two ships P and Q are observed south west and 5°east of South respectively. At the same time Q is observed from P in South East direction. If LP=4km, the distance between the ships is ________










