Answer:
The correct answer is "Secondary active transport".
Explanation:
Secondary active transport is a form of across the membrane transport that involves a transporter protein catalyzing the movement of an ion down its electrochemical gradient to allow the movement of another molecule or ion uphill to its concentration/electrochemical gradient. In this example, the transporter protein (antiporter), move 3 Na⁺ into the cell in exchange for one Ca⁺⁺ leaving the cell. The 3 Na⁺ are the ions moved down its electrochemical gradient and the one Ca⁺⁺ is the ion moved uphill its electrochemical gradient, because Na+ and Ca⁺⁺are more concentrated in the solution than inside the cell. Therefore, this scenario is an example of secondary active transport.
Explanation:
A covalent bond is a chemical bond that involves the sharing of electron pairs between atoms
Answer:The correct answer is option 4.
Explanation:
Arrhenius acids are those compounds which gives 
ions when dissolved in their aqueous solution.
Arrhenius bases are those compounds which gives 
ions when dissolved in their aqueous solution.
are Arrhenius acids because they form ions in their respective aqueous solution.
Hence, the correct answer is option 4.
Let's go through each of the answers and think about why they work or don't work.
Chemical forms compounds.
Nuclear changes the element completely. We're going to use the sun as an example. The sun is in a state of plasma. It's really hot and has all these particles hitting into each other. The nucleus' of atoms are hitting into each other forming larger elements. It's real crazy. Nuclear is not correct.
Physical cannot form a compound.
