Answer: e. All of the above.
Explanation:
Rainfall, temperature, seasonal variability are the important factors which determines the type of vegetation will grow in a biome, the type of animals will adapt and survive. Also these factors also determine the fact that type of landforms will form over a region. These factors are necessary for the development of the biodiversity. A biodiversity can be define as the variability and variety of life forms that can be found in the ecosystem or biome.
Here when an object is placed on the level floor then in that case there are two forces on the object
1). Weight of object downwards (mg)
2). Normal force due to floor which will counterbalance the weight (N)
so when no force is applied on the box at that time normal force is counter balanced by weight.
Now here it is given that A person tried to lift the box upwards
So now there are two forces on the box
1). Applied force of person
2). Normal force due to ground
So now these two forces will counter balance the weight of the crate
So we can write an equation for force balance like

given that

here
m = 30 kg and
g = acceleration due to gravity = 10 m/s^2

now from above equation


So force applied by the person must be 150 N
Answer:
The inlet velocity is 21.9 m/s.
The mass flow rate at reach exit is 1.7 kg/s.
Explanation:
Given that,
Mass flow rate = 2 kg/s
Diameter of inlet pipe = 5.2 cm
Fifteen percent of the flow leaves through location (2) and the remainder leaves at (3)
The mass flow rate is

We need to calculate the mass flow rate at reach exit
Using formula of mass



We need to calculate the inlet velocity
Using formula of velocity

Put the value into the formula


Hence, The inlet velocity is 21.9 m/s.
The mass flow rate at reach exit is 1.7 kg/s.
Answer:
A. Remove everything in the refrigerator to lighten the load.
B. Put a lubricant between the surface of the object and the floor
C. Use round objects, like pencils , to decrease the friction and push the refrigerator over the pencils more easily
Explanation:
Force of friction is a resistance force which acts between two surfaces which are in relative motion. Friction is both boon and bane. Due to friction, we are able to sit, walk etc but also, due to friction there is dissipation of energy. Friction can be reduced by applying lubricants, reducing contact area, reducing the load.
F = μN where N is the normal force which depends on the mass.
Thus, by reducing the load, force of friction can be reduced. Round objects like wheels can also be used. By this the contact area reduces.