The boundary between the crust and mantle is marked by a seismic-velocity discontinuity is called Mohorovicic discontinuity.
Mohorovicic discontinuity was discovered by Andrija Mohorovicic in 1909 who was a Croatian seismologist. He realized that the velocity of a seismic wave is related to the material's density where it is moving through. He decoded that the acceleration of the seismic waves that are observed within outer shell of the earth is a compositional change. Thus, the acceleration should be caused by a material of higher density.
Answer:
30N in the direction the 45N acts.
Explanation:
Fnet = F1 + F2 (the vector sum of the forces)
Assigning a positive direction to the 45N force and a negative direction to the 15N force gives:
Fnet = 45 - 15
Fnet = 30N
Since the answer is positive, it is in the direction the 45N force acts.
I believe the answer is 25*3.5 I apologize if this information is incorrect.<span />
Answer:
drag force 
Velocity (V) = 40.169 m/s
Explanation:
The drag force
is given by the formula:

where:
= drag coefficient depending on the Reynolds number
Reynolds number Re = 
Let's Assume that the air is in room temperature at 25 °C ; Then
density of the air
= 1.1845 kg/m³
viscosity of fluid or air
= 1.844 × 10⁻⁵ kg/ms
diameter of the baseball D = 7.4 cm
Velocity V = 44.3 m/s
Replacing them into the equation of Reynolds number ; we have :

A = Projected Area
From the diagram attached below which is gotten from NASA for baseball;
the drag coefficient which depends on Reynolds number is read as:
= 0.3
Projected Area A = 
A = 
A = 0.0043 m²
Finally, drag force is then calculated as ;

b)

since acceleration a = 
Then;

Also;
velocity (V) = 
Then;



Then;


Integrating the above equation ; we have :

when time (t) = 0 ; then 
44.3 = - 10 × 0 + C
C = 44.3

Time (t) =

∴ Velocity ; 

Velocity (V) = 40.169 m/s