ينزلق أحمد على سطح مائل بزاوية 40 درجة عن الأفق وإذا كان وزنه 55 كجم فما هو وزنه العمودي؟

Please note that the content provided appears to be a mathematical problem with an answer of 412.9N. Is there any additional content or context you would like included in the summary?