<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>
The knowledge of periodic table would be important in these three different careers such as medicine, pharmacology and engineering.
<h3>What is the importance of periodic table in following careers?</h3>
Periodic table is organised the whole elements vertically in groups and horizontally in periods with increasing atomic number.
The knowledge of arrangement of these elements serves alot of purposes in the following three different careers:
- Medicine: The element, iron is an important metal in the periodic table used in treatment of low blood levels.
- Pharmacology: The transition metals are useful in the field of pharmacology for the production of drugs. Example of such elements are chromium, manganese, cobalt, nickel, copper, and molybdenum.
- Engineering: The information of elements in the periodic table helps engineers in designing of materials used for constructions.
Therefore, the knowledge of periodic table is very important in these three different careers such as medicine, pharmacology and engineering.
Learn more about period table here:
brainly.com/question/15987580
The appropriate answer is B. Has no atmosphere. Neptune is a gas giant and is the eight planet in the solar system. It has a thick atmosphere consisting of hydrogen, helium and methane. Neptune has at least eight moons with Triton being the largest.
Neptune has four rings which circle the planet. The rings are made of dust particles, similar to the rings of Saturn.
The frequency : a) 7.5 x 10¹⁴ /s
<h3>Further explanation</h3>
Radiation energy is absorbed by photons
The energy in one photon can be formulated as
Where
h = Planck's constant (6,626.10⁻³⁴ Js)
f = Frequency of electromagnetic waves (/s or Hz)
f = c / λ
c = speed of light
= 3.10⁸ m/s
λ = wavelength
The wavelength(λ) of purple light is 400 x 10⁻⁹ m, so the frequency :
As a Depressant, it acts like a depressant
