Answer the following question given this paragraph: The molar mass of any substance is the mass in grams of one mole of representative particles of that substance. The representative particles can be atoms, molecules, or formula units of ionic compounds. This relationship is frequently used in the laboratory. Suppose that for a certain experiment you need 3.00 moles of calcium chloride (CaCl 2 ). Since calcium chloride is a solid, it would be convenient to use a balance to measure the mass that is needed. The molar mass of CaCl 2 is 110.98 g/mol. The conversion factor that can be used is then based on the equality that 1 mol = 110.98 g CaCl 2 . Dimensional analysis will allow you to calculate the mass of CaCl 2 that you should measure. Q: Who first proposed that earth is a magnet? A:

OPTIONS:
- Albert Einstein
- Isaac Newton
- Marconi
- william gilbert

Answer: william gilbert

Answer the following question given this paragraph: Oral Cavity Both physical and chemical digestion begin in the mouth or oral cavity, which is the point of entry of food into the digestive system. The food is broken into smaller particles by mastication, the chewing action of the teeth. All mammals have teeth and can chew their food to begin the process of physically breaking it down into smaller particles. The chemical process of digestion begins during chewing as food mixes with saliva, produced by the salivary glands (Figure 16.5). Saliva contains mucus that moistens food and buffers the pH of the food. Saliva also contains lysozyme, which has antibacterial action. It also contains an enzyme called salivary amylase that begins the process of converting starches in the food into a disaccharide called maltose. Another enzyme called lipase is produced by cells in the tongue to break down fats. The chewing and wetting action provided by the teeth and saliva prepare the food into a mass called the bolus for swallowing. The tongue helps in swallowingmoving the bolus from the mouth into the pharynx. The pharynx opens to two passageways: the esophagus and the trachea. The esophagus leads to the stomach and the trachea leads to the lungs. The epiglottis is a flap of tissue that covers the tracheal opening during swallowing to prevent food from entering the lungs. Q: Food is broken into smaller particles by mastication, a process involving action by what structures? A:

OPTIONS:
- cilia
- proteins
- tonsils
- teeth

Answer: teeth

Answer the following question given this paragraph: All of our cells contain DNA. Meiosis ensures that each gamete receives a copy of each chromosome. Q: What process within cells makes sure that every gamete receives a copy of every chromosome? A:

OPTIONS:
- genomes
- fission
- mutations
- meiosis

Answer: meiosis

Answer the following question given this paragraph: Water is the only substance on Earth that is stable in all three states. Q: What is the only substance on earth that is stable in all three states? A:

OPTIONS:
- carbon
- mercury
- air
- water

Answer:
water