<span>In the reverse reaction HF is a reactant.</span>
I would say it is constructing a hypothesis, that is because a hypothesis is basically gathering information or resources to support what your question was. so i say it is B.
As per as the Multiplication rules of the significant figures, whenever any numbers in the decimals forms are multiplied or divided then result in mentioned in such a way so that the significant figures after the decimal will be same as that in the given least condition.
_______________________________
102900/12 = 8575
170 × 1.27 = 215.9
∴ (102,900 ÷ 12) + (170 × 1.27) = 8575 + 215.9
= 8790.9
Now, As per as Above rules, answer in correct significant figures will be = 8791.
Exposure to small amounts of lead<span> over a long period of time is called chronic toxicity. </span>Lead<span> is particularly </span>dangerous<span> because once it gets into a person's system, it is distributed throughout the body just like helpful minerals such as iron, calcium, and zinc. And </span>lead<span> can cause harm wherever it lands in the body.</span>
Grinding solid crystals increase the rate of dissolving for a solid solute in water because smaller crystals have more surface area. The solubility of a substance depends on the physical and chemical properties of the solute and solvent as well as the temperature, pressure and the pH of the solution. For example increase in temperature increases the rate at which a solute dissolves in a solvent.
