Answer: 
Explanation:
Given
Length of plank is 1.6 m
Force
is applied on the left side of plank
Force
is applied 43 cm from the left end O.
Mass of the plank is 
for equilibrium
Net torque must be zero. Taking torque about left side of the plank

Net vertical force must be zero on the plank

The acceleration due to gravity of Mars is 
<u>Explanation:</u>
As per universal law of gravity, the gravitational force is directly proportional to the product of masses and inversely proportional to the square of the distance between them. But in the present case, the gravity need to be determined between Mars and the object on Mars. Since the mass of Mars is greater than the mass of any object. Thus,

Here, G is the gravitational constant, R is the radius of Mars and M, m is the mass of Mars and the object respectively..
Also, according to Newton’s second law of motion, the acceleration of any object will be equal to the ratio of force exerted on it to the mass of the object.
So in order to determine the acceleration due to gravity of Mars, divide the gravitational force of Mars by mass of object on the surface of Mars.




La magnitud es de 9.8 m/s² ... la aceleración de la gravedad en o cerca de la superficie de la Tierra.
La dirección es hacia el centro de la Tierra. (Llamamos a esa dirección "abajo").
The answer is A, it breaks down and releases thermal energy.
Answer:
d. H + O2 ------ H2O
that's the formation of water