Answer: There are two kinds of communication in the world of living cells. Communication between cells is called intercellular signaling, and communication within a cell is called intracellular signaling. An easy way to remember the distinction is by understanding the Latin origin of the prefixes: inter– means “between” (for example, intersecting lines are those that cross each other) and intra– means “inside” (like intravenous). Chemical sign
Explanation:
I have a answer hold on tho
A=P(1/2)^(t/h)
A=final amount
P=initial amount
t=time
h=half life
so
h=1.3 billlion (just write 1.3 and remember to mulipy the end time by 1 billion)
and final amount is 25% of original or 0.25P
0.25P=P(1/2)^(t/1.3)
divide both sides by P
0.25=(1/2)^(t/1.3)
take ln of bot sides
ln(0.25)=ln((1/2)^(t/1.3))
property of logarithms
ln(0.25)=(t/1.3)ln(1/2)
divide both sides by ln(1/2)
(ln(0.25))/(ln(1/2))=t/1.3
times both sides by 1.3
(1.3ln(0.25))/(ln(1/2))=t
remember that this is billion so
(1,300,000,000ln(0.25))/(ln(1/2))=t
2600000000.0001=t
about 2.6 billion years
It is Speciation because if it does'nt have this it wolud die
C is the answer because amplitude is need for wave 2 to be bigger than wave 1