784 Newton ( mass x gravity = 80 x 9.8)
Answer:

Explanation:
The car is under an uniforly accelerated motion. So, we use the kinematic equations. We calculate the acceleration from the following equation:

We convert the initial speed to 

The car stops, so its final speed is zero. Solving for a:

By definition;
M = fo/fe
Where,
M = Angular magnification
fo = Focal length of objective lens
fe = Focal length of eyepiece lens
From the information given;
M = 180/30 = 6
Answer:
1088.9N/m2
Explanation:
Calculation for What pressure is exerted
First step is to find the area of bottom of the tank using formula
Area=Width*breadth
Let plug in the formula
Area=0.5*0.9
Area=0.45m2
Now let calculate what pressure is exerted using this formula
Pressure=Force/Area
Where,
Force=Mass *Gasoline
Area=Width of the tank* Length of the tank
Let plug in the formula
Pressure=50*9.8/0.5*0.9
Pressure=490/0.45
Pressure=1088.9N/m2
Therefore What pressure is exerted is 1088.9N/m2
Answer:
The total momentum of the two objects before the collision is equal to the total momentum of the two objects after the collision.