Answer:
The geologist time scale was formed when scientists studied rock layers and index fossils worldwide. With this information, they placed Earth's rocks in order by relative age. Later, radioactive dating helped determine the exact age of the divisons in the geologic time scale.
This scale is organized by the 4.6 billion years of earth's history into sections based on important changes seen in the geologic record. The largest intervals are called eons, with each eon containing many millions of years.
In precambarian time the processes that affect Earth's surface have lessened the erosion on the surface. Earth was being hit by meteorites every second. Now there is water erosion and there wasn't back then. The surface changes have lessened over time.
Answer:
<em>a= In scientific notation</em>
6.96×10⁵ Km
<em>b =In expanded notation</em>
0.00019 mm
Explanation:
Given data:
Radius of sun = 696000 Km
size of bacterial cell = 1.9 ×10⁻⁴ mm
Radius of sun in scientific notation = ?
Size of bacterial cell in expanded notation = ?
Solution:
Radius of sun:
696000 Km
<em>In scientific notation</em>
6.96×10⁵ Km
Size of bacterial cell:
1.9 ×10⁻⁴ mm
<em>In expanded notation</em>
1.9/ 10000 = 0.00019 mm
Three classes: 28×3=84 students
8 test tubes per student: 84× 8= 672
hope this helps!
