Answer:
Changes in genetic makeup occurs with the passage of time.
Explanation:
Antibiotic cause mutation in the bacteria which allowed to develop resistance in the bacteria. This resistance and change in the genetic makeup obeys the theory of evolution which states that all species are changed gradually with the passage of time. The genetic makeup of bacteria also changes with the passage of time and attain resistance due to regular application of antibiotics so due to this resistance, the antibiotic can't work on the bacteria.
There may be a shortage of clean drinking water in the future
Calcium is a chemical element with symbol Ca and atomic number 20. Calcium is a soft gray Group 2 alkaline earth metal, fifth-most-abundant element by mass in the Earth's crust. The ion Ca2+ is also the fifth-most-abundant dissolved ion in seawater by both molarity and mass, after sodium, chloride, magnesium, and sulfate.[5] Free calcium metal is too reactive to occur in nature. Calcium is produced in supernova nucleosynthesis.
