Answer:True
Explanation:
Water is said to be hard when it contains calcium ions or magnesium ions dissolved in it. These ions are able to react with soap in such a way that the soap is prevented from forming lather with the water. Hard water occurs when water passes over calcium or magnesium bearing minerals and dissolves some of it. Hardness due to the presence of calcium ions can easily be removed by boiling the water.
Answer:
the particles with a negative charge are protons
The three hypotheses that explain why being born in the United States
leads to a higher chance of developing allergies include the following:
- The weather patterns in the United States bring more allergens compared to other countries.
- Other factors which might influence why there are more children with allergies in the United States include climate, obesity, and the typical western diet with high amounts of processed foods.
- The hygiene hypothesis claims that children in the United States are not exposed to enough germs in their infancy and childhood to develop their immune system‘s properly.
Allergies are caused by a host of factors such as :
These factors is the reason why the chosen hypotheses are the most
appropriate.
Read more about Hypotheses here brainly.com/question/10854125
4 becuase they absorb a little amount