Answer:
Step-by-step explanation:
Alright, lets get started.
Suppose they take t minutes to meet each other.
Distance covered by first friend in t minutes, = 0.2 *t=0.2∗t
Distance covered by second friend in t minutes , =0.15 *t=0.15∗t
Total distance is given as 7, so
0.2 t + 0.15 t = 70.2t+0.15t=7
0.35 t = 70.35t=7
t = 20t=20
means after 20minutes they will meet.
SO. the average speed is 10m: Answer
The identity of the substance is Iron.
<h3>Properties of Iron</h3><h3>Chemical properties</h3>
- The element iron has the atomic number 26 and the symbol Fe
- Electronic configuration of Fe is [AR] 3d6 4s2
- The atomic weight of Iron is 55.847
- The element iron belong to the group VIII of the periodic table
- It is the fourth most prevalent element in the crust of the world
- It is a highly reactive element as it gets rusted readily in the moisture of air
<h3>Physical properties</h3>
- It is a heavy metal in the first transition series
- The color of iron is silvery grey
- High malleability and ductility
- It has a strong electrical conductivity.
Learn more about periodic table on
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<span>The right answer is D. In a situation where the sound wave reaches the ear and the reflected wave reaches the ear less than 0.1 seconds later, the individual would not be able to hear an echo. There needs to a far more significant delay between the sound and the reflection of said sound reaching the listener's ear for the echo effect to become apparent.</span>
Of course we would experience them.
