Answer:
51.2 mi/h
Explanation:
Total distance, d = 100 miles
First 60 miles with speed 55 mi/h
Next 40 miles with speed 75 mi/h
Time taken for first 60 miles, t1 = 60 / 55 = 1.09 h
Time taken for 40 miles, t2 = 40 / 75 = 0.533 h
Time spent to get stuck, t3 = 20 min = 0.33 h
Total time, t = t1 + t2 + t3 = 1.09 + 0.533 + 0.33 = 1.953 h
The average speed is defined as the ratio of total distance traveled to the total time taken.
Average speed = 
Thus, the average speed of the journey is 51.2 mi/h.
Answer:
D. loss of volatiles to the atmosphere
Explanation:
The name magma designates matter in a semi-fluid state - resulting from the fusion of silicates containing dispersed solid gases and minerals and other compounds that make up the rocks, at temperatures between 700 and 1200 ° C - that forms the region beneath the crust. land. When it is inside the earth it is specifically named magma and lava when it is ejected to the surface
There are three systems by which magma can be produced on earth:
<u>
Temperature</u> rise by concentration of r<u>adioactive elements or by friction of lithospheric plates</u>.
<u>
Pressure decrease,</u> since the melting point decreases.
Adding <u>water</u> A rock begins to melt earlier if it contains water because the –OH groups effectively break the Si-O bonds.
A rock is formed by a set of minerals, each of which has a characteristic melting point so a rock does not have a single melting point but a temperature range in which the rock melts into parts, leaving others solid parts. Between the point at which a solid rock begins to melt and the melting end (liquid point) the rock is partially molten.
The rise of magmas depends on their physical-chemical conditions (viscosity, density, volatile element content), on the tectonic peculiarities of the region where they are found and on the rocks to be traversed. Acid magmas are light and viscous, rise easily and cause large deposits. The basic magmas, of greater density, are less viscous and ascend with greater difficulty than the previous ones.
1. a. longitudinal waves.
There are two types of waves:
- Transverse waves: in transverse waves, the oscillations of the wave occur in a direction perpendicular to the direction of propagation of the wave
- Longitudinal waves: in longitudinal waves, the oscillations of the waves occur parallel to the direction in which the waves are travelling.
So, these types of waves are called longitudinal waves.
2. d. a medium
There are two types of waves:
- Electromagnetic waves: these waves are produced by the oscillations of electric and magnetic field, and they can travel both in a medium and also in a vacuum (they do not need a medium to propagate)
- Mechanical waves: these waves are produced by the oscillations of the particles in a medium, so they need a medium to propagate - therefore, the correct choice is d. a medium
3. a. AM/FM radio
Analogue signals consist of continuous signals, which vary in a continuous range of values. On the contrary, digital signals consist of discrete signals, which can assume only some discrete values. For AM and FM radios, signals are transmitted by using analogue signals.
A.) We use the famous equation proposed by Albert Einstein written below:
E = Δmc²
where
E is the energy of the photon
Δm is the mass defect, or the difference of the mass before and after the reaction
c is the speed of light equal to 3×10⁸ m/s
Substituting the value:
E = (1.01m - m)*(3×10⁸ m/s) = 0.01mc² = 3×10⁶ Joules
b) The actual energy may be even greater than 3×10⁶ Joules because some of the energy may have been dissipated. Not all of the energy will be absorbed by the photon. Some energy would be dissipated to the surroundings.
