Answer:
The correct answer is - sulfur.
Explanation:
In the periodic table, there are 18 groups and 7 rows or periods arranged according to their atomic number or electronic configuration. In the question, it is mentioned that the desired element atomic mass is less than the atomic mass of the selenium which is 78.96, and more than oxygen which is 15.99 with 6 electron valence and present in the third row.
As it has 6 valency of electron it must be in the 16 group of the table that comprises the 6 valency and as it is located in the 3rd row it must be sulfur that also has an atomic mass between selenium and oxygen.
Answer
Susan can process wind speed data from different regions.
Explanation
A Doppler radar is used in weather forecasting in measuring the direction and speed of objects such as drops of precipitation. It determines if the movement occurring in the atmosphere is horizontally towards or way from the radar. Susan can obtain velocity data about objects at a distance which might be water droplets thus be able to predict a coming weather
You can know the metal with low reactivity and the metal with high reactivity from the periodic table, as in metals the Chemical reactivity increases by going down a group, because of the farther down group we go the easier of lose and gain of electrons or the easier the electrons to be given or taken, this caused the chemical reactivity be higher.
- and the chemical reactivity decreases as we go across the period because they want to give away valence electrons, they need more energy to get rid of them.
There are many simple ways to prevent erosion. One of the simplest forms of preventing erosion is with vegetation and by establishing root systems that hold the soil together. You can also use geotextiles, fertilizers and also build retainer walls to keep the soil intact and prevent erosion.