A100.0 gram sample of polonium-210 is contained for 552 days. how many half-lives occur during this period of time, if the half-life is 138 days?

4 half-lives will occur during this period of time.

Explanation:

Formula used :

where,

a = amount of reactant left after n-half lives and time t

= Initial amount of the reactant.

decay constant

= half life of an isotope

n = number of half lives

We have :

a = ?

t = 552 days

n = 4

4 half-lives will occur during this period of time.

answer: d. a cme increases the amount of energy in the solar wind

explanation:

coronal mass ejections, also called cmes, are large clouds of plasma and magnetic field that erupt from the sun. only when the cloud is aimed at earth will the cme hit earth and therefore cause impacts. high-speed solar wind streams come from areas on the sun known as coronal holes.

c.the charges if the proton and electron and gravity