Answer : The correct option is, (C) 10-mL volumeric pipet.
Explanation :
Graduated cylinder : It is a measuring cylinder that is used to measure the volume of a liquid. It has a narrow cylindrical shape. The marked line drawn on the graduated cylinder shows the amount of liquid that has been measured.
Pipet : It is a type of laboratory equipment that is used to measure the volume of a liquid. It is small glass tube and the marked line drawn on the pipet. It is used to accurately measure and transfer of volume of liquid from one container to another.
Volumetric flask : It is a type of laboratory tool that is also used for measuring the volume of liquid. It is used to make up a solution to a known volume. It measure volumes much more precisely than beakers.
Beaker : It is a type of laboratory equipment that has cylindrical shape and it is used for the mixing, stirring, and heating of chemicals.
As per question, we conclude that the pipet is most precise than other devices because in pipet the marking lines are more accurate. Thus, it can be used to measure volume to precision.
Hence, the correct option is, (C) 10-mL volumeric pipet.
He thought elements that haven't been discovered belonged in the place of the gap. He could also use the atomic mass of the missing elements
Answer: -
The experiment Niven is doing is burning of Mg.
The first step would be finding the molar mass of MgO
Atomic mass of Mg = 24 g
Atomic mass of Oxygen = 16 g
Molar mass of MgO = 24 x 1 + 16 x 1 = 40 g
The balanced chemical equation for this reaction is
2 Mg + O2 -- > 2MgO
From the balanced equation we see that
2 Mg gives 2 MgO
2 x24 g of Mg O gives 2 x 40 g of MgO.
28g of MgO gives

= 46.66 g of MgO.
25 people in an elevator that has a maximum load of 20 people