A new 1.3 m3 tank and ancillary equipment is to be installed in a hygienic food processing plant. The duty is to store a heat sensitive water based fluid at 25 degC for a period of 10 hours. The fluid has a high capital value, and is damaged if the fluid temperature drops below 20 degC, or exceeds 30 degC. Propose two equipment methods, in order of preference, to achieve the above duty, and outline the advantages and disadvantages of each method and the basis of your proposition.