Answer:
The correct option is the option;

Explanation:
The wavelength of a wave is the distance between two successive crests of the wave
Therefore, the wavelength, λ, is given by the fraction of the velocity, <em>v</em>, of the wave divided by the frequency, <em>f</em>, (the number of cycles that pass through a point) of the wave
Mathematically, we have;


The <em>minimum space cushion</em> defines the required amount of space which vehicles should maintain in other to afford them the time and space to gain control in emergency scenarios. Hence, the minimum space cushion required in the scenario is 4 seconds.
In cases of mishaps or accidents, the space cushion might just afford other cars the space to maneuver their way to safety rather than being caught up in the collison or accident.
The required space cushion in most scenario is usually between 2 - 5 seconds, with additional space afforded depending on the <em>length and type of the vehicle</em>.
Therefore, to ensure safety, the required minimum space cushion to be left when driving being a cargo van traveling at a <em>speed of 25mph is 4 seconds</em>.
Learn more :brainly.com/question/24535523
Answer:
40.06 amu.
Explanation:
From the question given above, the following data were obtained:
Isotope A (K-39)
Mass of A = 39 amu
Abundance of A = 23%
Isotope B (K-40)
Mass of B = 40 amu
Abundance of B = 48%
Isotope C (K-41)
Mass of C = 41 amu
Abundance of C = 100 – (23 + 48)
Abundance of C = 100 – 71
Abundance of C = 29%
Average mass =?
Average mass = [(Mass of A × A%)/100] + [(Mass of B × B%)/100] + [(Mass of C × C%)/100]
= [(39 × 23)/100] + [(40 × 48)/100] + [(41 × 29)/100]
= 8.97 + 19.2 + 11.89
= 40.06 amu
Thus, the average mass of potassium is 40.06 amu