Answer:
A. It is the work done when a force of 1 newton is applied to an object for a distance of 1 meter
Explanation:
The compound that was formed by the reaction of the first oxygen released by Cyanobacteria and iron are the metals of the earths crust. Cyanobacteria was the first organisms that used water instead of hydrogen sulfide or other compounds as a source of electrons and hydrogen for fixing carbon dioxide. Early Cyanobacteria inhabited marine sediments where Archean banded iron formations were deposited; consisting of reddish layers rich in iron oxide.
The correct answer for this question is this one: " a.The solution has a volume of 25 mL "
The observation that shows a quantitative observation is when you are talking about numeric data. Just like this one, <em>The solution has a volume of 25 mL </em>
Hope this helps answer your question and have a nice day ahead.
Answer:
Considering the half-life of 10,000 years, after 20,000 years we will have a fourth of the remaining amount.
Explanation:
The half-time is the time a radioisotope takes to decay and lose half of its mass. Therefore, we can make the following scheme to know the amount remaining after a period of time:
Time_________________ Amount
t=0_____________________x
t=10,000 years____________x/2
t=20,000 years___________x/4
During the first 10,000 years the radioisotope lost half of its mass. After 10,000 years more (which means 2 half-lives), the remaining amount also lost half of its mass. Therefore, after 20,000 years, the we will have a fourth of the initial amount.
C can be the only correct answer - 6.023 x 10^23 is the amount of molecules in a mol of an element. 4.5 x 6.023 x 10^23 can not equal anything but C.
4.5 x 6.023 x 10^23 = 2.71035 x 10^24
