The formular for determinatio of mass number is this:
Mass number = number of proton + number of neutron
From the question, we are told that:
Mass number = 39
Proton number = 19
Number of proton = ?
Number of neutron = mass number - number of proton
Number of neutron= 39 - 19 = 20
Therefore, number of neurtron = 20.
<span>Sonata form, consisting of three main sections (exposition, development, recapitulation), is sometimes revisited, and often quoted in the finale as well.</span>
Answer:
<em>two different components</em>
Explanation:
<em>Any two-dimensional vector can be conceived of as having two distinct components. The component of a single vector describes the vector's effect in a specific direction.</em>
Relation between electrostatic force and distance is inverse square i.e
1
Fα ----
r^2
Hence if r is tripled, new electrostatic force will be 1/9 times old force.