5. The following are the structures of four lipids (a) To which lipid class does A belong?
(b) Give the name of structure C
(c) Give the name of structure D
(d) Name the molecular components of the complete hydrolysis of B
(e) What are the products of the treatment of A with
phospholipase D
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i believe you are right for all except the 3rd ( look at sqdancefan his answer is much better)

a gas, having a molecular weight of 13 kg/kmol and a kinematic viscosity of 0.25 cm2/s, flows through a pipe 0.25 m internal diameter and 5 km long at the rate of 0.4 m3/s and is delivered at atmospheric pressure.