im pretty sute the answer would be number 4.
mark brainliest :)
694,563,239 rounded to the nearest thousand is 694,563.
It's because the first digit from the right is for ones, second for tens, third for hundreds and fourth for thousands and that's the one that we should take a closer look at. You can round it either to 3 or 4, depends on the digit of hundreds. In this case 3239 is clearly closer to 3000 than 4000, that's why we round it to 694,563, not 694,564.
From the calculations, the concentration of the acid is 0.24 M.
<h3>What is neutralization?</h3>
The term neutralization has to do with a reaction in which an acid and a base react to form salt and water only.
We have to use the formula;
CAVA/CBVB = NA/NB
CAVANB =CBVBNA
The equation of the reaction is; 2NaOH + H2SO4 ----> Na2SO4 + 2H2O
CA = ?
CB = 1.2 M
VA = 50 mL
VB = 20 mL
NA = 1
NB = 2
CA = CBVBNA/VANB
CA = 1.2 M * 20 mL * 1/ 50 mL * 2
CA = 0.24 M
Learn more about neutralization:brainly.com/question/27891712
#SPJ1
<span>a. Tall prarie grass burns after being struck by lightning.</span>
Answer:- Density is 10.5 grams per mL and the substance is Silver(Ag).
Solution:- Mass of jewelry is given as 132.6 g. Initial volume of water in the graduated cylinder is 48.6 mL and the volume becomes 61.2 mL when this jewelry is submerged in the cylinder.
So, the volume of the jewelry = 61.2 mL - 48.6mL = 12.6 mL
We know that, 
Let's plug in the values in the above formula to calculate the density:


So, the density of the jewelry is
.
The substance from which the jewelry is made could easily be identified by comparing the calculated density with the density values given for different substances in the density table.
Looking at the density table, 10.5 grams per mL is the density for silver. So, the jewelry is made up from Silver.