Answer:
Helium, this noble gas has the least density at STP
Explanation:
Because Boron likes to lose 3 electrons when it undergoes ionization, we draw a boron ion like a helium atom, with just 2 electrons in the first shell, and 0 in the second
<u>Answer:</u> The force that must be applied is 15 N.
<u>Explanation:</u>
Force exerted on the object is defined as the product of mass of the object and the acceleration of the object.
Mathematically,

where,
F = force exerted = ?
m = mass of the object = 3 kg
a = acceleration of the object = 
Putting values in above equation, we get:

Hence, the force that must be applied is 15 N.