H2O
The other ones are just elements
Answer: <em>The </em><em>alkali metals</em><em> reactivity is generally higher than the alkaline earth metals. </em>
Explanation: <em>This makes the alkaline earth metals with their two valence electrons less reactive than alkali metals with their one valence electron.</em>
<u>Alkali metals is ns1 and alkaline earth metals is ns2</u>
Acceleration is defined as velocity per unit time.


Here, a=acceleartion,
v=velocity=36 m/s
t=time=12 s



A car at rest ends accelerates for 12 seconds. After this time the car is going 36 m/s. So acceleration that is a=3 ms⁻².
There are 7 digits from decimal to 1st digit, and it's coming from right, so exponent will be in negative 7
In short, Your Answer would be: Option C) <span>6.75 × 10-7
</span>
Hope this helps!