Impulse in physics is the integral of force, F, with respect with time, t. This value is a vector quantity since force is a vector quantity as well. It can be calculated from the product of force and time. We do as follows:
Impulse = Ft
= m(a)(t)
= m(v/t)t
= 0.046 (42/0.0005) (0.0005)
= 1.932 N-s
Valence electrons are required for certain bonding processes. Without them you cannot bond with certain elements. For example, carbon bonds really well with carbon because it has the same amount of valence electrons. However carbon would not bond well with uranium due to the massive differences in valence electrons. Hope this helps!
Average speed = total distance / total time.
That's 172 km / 5 hr = 34.4 km//hr
The answer to your question is A. Have a great day