Answer:
Explanation:
In 1789, Antoine Lavoisier published a list of 33 chemical elements. Although Lavoisier grouped the elements into gases, metals, non-metals, and earths, chemists spent the following century searching for a more precise classification scheme. In 1829, Johann Wolfgang Döbereiner observed that many of the elements could be grouped into triads (groups of three) based on their chemical properties. Lithium, sodium, and potassium, for example, were grouped together as being soft, reactive metals. Döbereiner also observed that, when arranged by atomic weight, the second member of each triad was roughly the average of the first and the third.[19] This became known as the Law of Triads.[20] German chemist Leopold Gmelin worked with this system, and by 1843 he had identified ten triads, three groups of four, and one group of five. Jean Baptiste Dumas published work in 1857 describing relationships between various groups of metals. Although various chemists were able to identify relationships between small groups of elements, they had yet to build one scheme that encompassed them all.[19]
The talk test can be used to measure the <u>intensity of an activity</u>
<u>Option: B</u>
<u>Explanation:</u>
The talk test is usually used to measure the intensity of a particular activity when a person talks during that activity. This is mostly used in cardiovascular patients to measure the intensity of the exercise.
For example, when a person can talk during exercising, it means that he is able to use the oxygen to create energy for the muscles. i.e he will be in aerobic state. Incase, he is not able to talk any more during his exercise, it means that the breathing rate has reached a particular ventilatory threshold.
So now the body is creating energy from the stored system such as muscle glucose and creatine. Thus this talk test helps to determine in which way your body creates energy, aerobic or non aerobic.
Answer:
I am not sure of the question?
Explanation:
List the question
Dies are turned using a special tool called a stock! Your welcome
Answer:
25 m
9.9 m/s
22 m/s
Explanation:
m = Mass of ball
v = Velocity
g = Acceleration due to gravity = 9.81 m/s²
Applying conservation of energy
The height above the ground is 5.09683+20 = 25.09683 m = 25 m
The ball's speed as it passes the window on its way down is 9.9 m/s
The speed of impact on the ground is 22 m/s