WAEC Commerce 2013 Theory question 107

(a) Tramps have no fixed route or timetable and go wherever cargo is available, mostly carrying bulky cargo; liners sail on fixed routes at scheduled times, carrying passengers and general cargo at fixed rates.
(b) A factor holds the goods and may sell in his own name, give credit and fix prices; a broker does not hold the goods and deals in the principal's name, earning brokerage.
(c) A commission agent sells for a commission but does not guarantee buyers' payment; a del credere agent guarantees payment by the buyers he finds and earns an extra (del credere) commission.
(d) A consular invoice is certified by the importing country's consul and is used in foreign trade to confirm value/origin for duty; a proforma invoice is sent before goods are supplied, e.g. to ask for payment in advance or as a quotation.
(e) Insurance covers risks that may or may not happen (fire, theft) and follows indemnity; assurance covers events that will certainly happen (death) and pays an agreed sum, not indemnity.

Give two contrasting points for each pair.