This is a easy question, but it should not be confused with payment types. Most contracts include fixed and firm price elements along with time and materials. This question is asking about general forms of contract approach including prime, parallel (framework), single supplier, sequential (traditional) and Turnkey (EPC) contracts. The names in brackets are my terms not the ones used by the APM. The question requires one paragraph of three sentences on each. Have a go and I will give you feedback.