Asample of sodium-22 (z= 11) decays to neon-22 (z 10). the alf-life of this sodium isotope is 2.5 years. the masses of the sodium-22 and neon- 22 atoms are 21.994434 u and 21.991383 u, respectively. the initial mass of the sodium-22 sample is 5 mg. [2 points] what is the radius of the sodium-22 nucleus?

is the radius of the sodium-22 nucleus.

Explanation:

Where:

= Constant for all nuclei

r = Radius of the nucleus

A = Number of nucleons  or atomic mass

Radius of the sodium-22 nucleus

Atomic mass of Na-22= 21.994434 u

A = 21.994434

is the radius of the sodium-22 nucleus.

the old price per ounce is c/4.

the new price per ounce is c/3.6.

the ratio of the old price to the new one is

(c/4)/(c/3.6) = (c/c)×(3.6/4) = 0.9 . . = 9/10 . . "nine tenths" in either form