A scientist wants to test whether the pH, salinity, or temperature of seawater impacts coral development. He sets up an experiment with three conditions:
Aquarium 1: Normal pH, normal salinity, normal temperature
Aquarium 2: High pH, high salinity, high temperature
Aquarium 3: Low pH, low salinity, low temperature
What factor would improve experimental design the most?

Eliminating Aquarium 1 since it only uses normal conditions

Testing one variable at a time and keeping the other two variables constant

Using one aquarium and changing the variables from day to day

Setting up the variables on a gradient in each aquarium

Testing one variable at a time and keeping the other two variables constant

answer: "circumcision is a common procedure in which the skin covering the tip of the penis is surgically removed."

water is a polar molecule. a chemical bond is a force of attraction between atoms or ions. bonds form when atoms share or transfer valence electrons. atoms form chemical bonds to achieve a full outer energy level, which is the most stable arrangement of electrons. so, false

explanation:

in h2o molecule, two water molecules are bonded by a hydrogen bond but the bond between two h - o bonds within a water molecule are covalent. the greater the electronegativity difference, the more ionic the bond is. bonds that are partly ionic are called polar covalent bonds. nonpolar covalent bonds, with equal sharing of the bond electrons, arise when the electronegativities of the two atoms are equal.