The correct answer is that the shells of clams and other mollusks dissolve when the pH becomes more acidic.
This is because the shells of clams and other mollusks are made of calcium carbonate that is dissolved in acidic conditions. The pH needs to be low to dissolve calcium carbonate into it. It takes few days to dissolve the shell completely.
Answer:
A houseplant is usually small, and darkly colored, whereas an outdoor plant will usually have a brighter color and will more likely to grow in size. Most plants prefer a temperature of around 76-93 degrees Fahrenheit. Meaning if you like your house to be cool, your plants' growth could be stunted.
Ans.
Paper waste prevention is defined as a practice to reduce or eliminate use of paper, which is potential for the efficient use or disposal of paper. It decreases the environmental impacts due to both paper manufacturing and paper recycling, such as demands on forest resources).
Use of advance technologies, such as E-mail (electronic mail) can help in cut down on paper waste. Nowadays, E-mail has replaced conventional letters and faxes as it is more eco-friendly than letters and faxes, which needs paper consumption.
Thus, the correct answer is 'option d). E-mail.'
Answer:
B. natality + immigration = mortality + emigration
Explanation:
Migration refers to the movement of a group of people from one geographical region (location) to another geographical destination in search of better living conditions, work or social amenities.
Migration selectivity can be defined as the likelihood or tendency that a subset (part) of a group of people are going to move (migrate) out of a particular geographical location or area.
Some of the factors that influence migration selectivity are income level, age, education, gender etc.
Population change equation states that the change in the size of a population over a specific period of time is equal to the sum of the number of births and the number of immigrants that joined.
Mathematically, the population change equation is given by the formula;
Population Change = (Natality - Mortality) + (Immigration - Emigration)
Therefore, the equation which would create a stable population is given by the formula;
Natality + immigration = mortality + emigration.
