Which of the following elements have properties similar to those of astatine?

f, br, l
na, mg, al
ar, s, p
f, ar, ne

F, Br, l

F, Br, l

Explanation:

Astatine is radioactive element which has symbol, At and the atomic number of the element is 85.

It belongs to the group 17 and period 6.

The elements in the same group shows similar properties as they have same general electronic configuration.

So, it shows similar properties with group 17 elements which are - F, Cl , Br, l

Answer- A

chemists can use the electron cloud model to assign electrons to different atomic orbitals. atomic orbitals also explain the patterns in the periodic table

explanation:

in scientific notation, the value of the  speed of light in a vacuum

  will be written as 2.995 * 10^8. when this value is represented in the form of

  a * 10^b, then, a = 2.995 and b = 8.

the value of the speed of light in a vacuum given above can also be rounded up to approximately 300000000. in this case, the scientific notation will be written as 3 *10^8.