Bacteria are classified as prokaryotes, along with another group of single-celled organisms, the archaea.
Prokaryotes are organisms whose cells lack a nucleus and other organelles. Prokaryotes are divided into two distinct groups: the bacteria and the archaea, which scientists believe have unique evolutionary lineages. Most prokaryotes are small, single-celled organisms that have a relatively simple structure. no
-6+1= -5
-5 is the true answer
Answer:
- a family is a group consisting of 2 parents and their children living together in a union.
or all desendants of a common ancestor
2. A period is a name given to the horizontal row of the periodic table.
3.
a.mg
b.k
c.Fe
d.cu
e.Al
4.
a.Carbon
b.Chlorine
c.Gold
d.strontium
5.
a.period 1
b.period 4
c.period 5
d.period 5
6.
a.group 6
b.group 2
c.group 7
d.group 8 belong ti 1st transitional elements.
7.
a.F
b.Na
c.Ar
d.V
e.I
The amount left after 20 years = 154.15 mg
<h3>Further explanation
</h3>
The atomic nucleus can experience decay into 2 particles or more due to the instability of its atomic nucleus.
Usually radioactive elements have an unstable atomic nucleus.
The main particles are emitted by radioactive elements so that they generally decay are alpha (α), beta (β) and gamma (γ) particles
The decay formula for isotope :

Then for t=20 years, the amount left :
