9. During a laboratory investigation, a scientist extracted gastric juice from the mammalian stomach. He used it to carry out tests on a food sample 8 which was suspected to contain proteins. He divided the food sample B into three portions and treated them as below. 1. On the 15t portion of B, he added Gastric juice and mixed them thoroughly before adding sodium hydroxide followed with copper (11) sulphate drop by drop. it. On the 2nd portion of B, he added boiled gastric juice and mixed them thoroughly before adding sodium hydroxide followed with copper (11) sulphate drop by drop. 1. On the 3 portion of B, he added Gastric juice, sodium bl-carbonate and mixed them thoroughly before adding sodium hydroxide followed with copper (11) sulphate drop by drop. a) State the observations he made in each set up. (3marks) 1"portion 2nd portion3 portion