Discuss two disadvantages of biotechnology and calculate the percentage composition by mass of oxygen in Ca(NO3)2.

You're on a roll — let's keep going. Here's the solution for question 3: 3) Two disadvantages of biotechnology are: Step 1: Discuss ethical concerns. Biotechnology raises significant ethical concerns, particularly regarding genetic engineering and cloning. Issues such as the manipulation of human genes, the creation of genetically modified organisms (GMOs), and the potential for unintended consequences on biodiversity and ecosystems are often debated. Step 2: Discuss potential health risks and environmental impacts. There are concerns about potential health risks associated with consuming genetically modified foods, such as allergic reactions or the transfer of antibiotic resistance. Environmentally, the release of GMOs could lead to the development of herbicide-resistant weeds or pests, and the loss of genetic diversity in natural populations. Here's the solution for question 4: 4) To calculate the percentage composition by mass of oxygen in Ca(NO_3)_2: Step 1: Calculate the molar mass of Ca(NO_3)_2. Given atomic masses: Ca = 40, N = 14, O = 16. The formula Ca(NO_3)_2 means there is 1 Calcium atom, 2 Nitrogen atoms (since N is inside the parenthesis and multiplied by 2), and 6 Oxygen atoms (3 × 2 = 6). Molar mass of Ca(NO_3)_2 = (1 × 40) + (2 × 14) + (6 × 16) Molar mass of Ca(NO_3)_2 = 40 + 28 + 96 Molar mass of Ca(NO_3)_2 = 164 g/mol Step 2: Calculate the total mass of oxygen in one mole of Ca(NO_3)_2. There are 6 oxygen atoms in the compound. Total mass of oxygen = 6 × 16 g/mol = 96 g/mol Step 3: Calculate the percentage composition by mass of oxygen. Percentage of oxygen = Total mass of oxygenMolar mass of Ca(NO_3)_2 × 100\% Percentage of oxygen = 96 g/mol164 g/mol × 100\% Percentage of oxygen = 0.585365... × 100\% Percentage of oxygen ≈ 58.54\% The percentage composition by mass of oxygen in Ca(NO_3)_2 is 58.54\%. All done! Drop the next question.