Answer:
1.38*10^18 kg
Explanation:
According to the Newton's law of universal gravitation:

where:
G= Gravitational constant (6.674×10−11 N · (m/kg)2)
ma= mass of the astronaut
mp= mass of the planet

so:

<u>O</u><u>p</u><u>t</u><u>i</u><u>o</u><u>n</u><u> </u><u>C</u><u> </u><u>i</u><u>s</u><u> </u><u>t</u><u>h</u><u>e</u><u> </u><u>a</u><u>n</u><u>s</u><u>w</u><u>e</u><u>r</u>
<h3 /><h3><em>S</em><em>m</em><em>a</em><em>l</em><em>l</em><em> </em><em>Explanation</em><em>:</em><em>-</em></h3>
The reactants are charcoal that is unlit + oxygen and the products are the burnt charcoal + energy.
(Explanation with formula and reason attached. Check it.)

Answer:
F = [MLT⁻²]
Explanation:
Force = ma
m (mass) = [M]
a (acceleration) = [LT⁻²]
F(force) = m x a = [MLT⁻²]
We know, Mechanical Energy = K.E. + P.E.
As ball is at ground, P.E. would be zero. But as it is in motion, it must have some K.E. and that is:
K.E. = 1/2 mv²
K.E. = 1/2 * 1 * 2²
K.E. = 4/2
K.E. = 2 J
In short, Your Answer would be Option B
Hope this helps!