Answer:
a. When a fetus is 13-15 weeks old
Explanation: is correct
Please show that answer choices like what does a say
Answer:
Avoid the consumption of gases dangerous to the ozone layer, due to their content or manufacturing process. Some of the most dangerous gases are chlorofluorocarbons, halogenated hydrocarbon, methyl bromide, and nitrous oxide.
Minimize the use of cars. The best transport options are urban, bicycle, or walking. If you use a car, try to carpool to decrease the use of cars. This prevents pollution.
Do not use cleaning products that are harmful to the environment. Many cleaning products contain substances that are corrosive. Replace these dangerous substances with non-toxic products such as vinegar or bicarbonate.
Buy local products. Not only do you get fresh products but you avoid consuming food that has traveled long distances. The more food is transported, the more nitrous oxide is produced due to the cars or trucks used to transport it.
Maintain air conditioners, as their malfunctions cause chemicals to escape into the atmosphere.
Explanation:
Hope this helped! =)
This is because the GP120 protein
of the HIV virus that forms the ‘knob’ is
essential for the infection of CD4 cells
of the immune system by the virus. The glycoprotein is, therefore, a good
target for vaccines especially since the
molecule is highly conserved because most mutations in the region could be highly deleterious to the virus.
Primary consumers enrich the soil,which help plants to grow and create more food energy for all of us.
