Section D Section D Checkpoint

Problem 1

Select all expressions written using scientific notation:
A
42,000,000
B
56×1,000,00056\times1,000,000
C
87×10687\times10^6
D
4.2×1074.2\times10^7
E
5×10-35\times10^{\text-3}
F
0.2×1090.2\times10^9
G
1.4 million
H
0.009×10100.009\times10^{10}
I
6×10×10×106\times10\times10\times10
J
7.3E47.3E4

Show Solution
Solution
D, E, J
Show Sample Response
Sample Response
D, E, J

Problem 2

The table shows the average mass of one individual creature and an estimated total number of those creatures on Earth.

creature total number mass of one individual (kg)
humans 7.5×1097.5 \times 10^9 6.2×1016.2 \times 10^1
cows 1.3×1091.3 \times 10^9 4×1024 \times 10^2
sheep 1.75×1091.75 \times 10^9 6×1016 \times 10^1
chickens 2.4×10102.4 \times 10^{10} 2×1002 \times 10^0
ants 5×10165 \times 10^{16} 3×10-63 \times 10^{\text -6}
blue whales 4.7×1034.7 \times 10^3 1.9×1051.9 \times 10^5
antarctic krill 7.8×10147.8 \times 10^{14} 4.86×10-44.86 \times 10^{\text -4}
zooplankton 1×10201 \times 10^{20} 5×10-85 \times 10^{\text -8}
bacteria 5×10305 \times 10^{30} 1×10-121 \times 10^{\text -12}
 
  1. What is the total mass of 1 human, 1 cow, and 2 chickens? Explain or show your reasoning.

  2. What is the total mass of all the zooplankton on the planet? Explain or show your reasoning.
Show Solution
Solution
  1. 466 kg. Sample reasoning: Each human is 62 kg, each cow is 400 kg, and each chicken is 2 kg. The total mass for 1 human, 1 cow and 2 chickens would be 62+400+2+2=46662+400+2+2=466 kg.
  2. 5×10125\times10^{12} kg (or equivalent). Sample reasoning: (1×1020)×(5×10-8)=(1×5)×(1020×10-8)=5×1012(1\times10^{20})\times(5\times10^{\text-8})=(1\times5)\times(10^{20}\times10^{\text-8})=5\times10^{12}.
Show Sample Response
Sample Response
  1. 466 kg. Sample reasoning: Each human is 62 kg, each cow is 400 kg, and each chicken is 2 kg. The total mass for 1 human, 1 cow and 2 chickens would be 62+400+2+2=46662+400+2+2=466 kg.
  2. 5×10125\times10^{12} kg (or equivalent). Sample reasoning: (1×1020)×(5×10-8)=(1×5)×(1020×10-8)=5×1012(1\times10^{20})\times(5\times10^{\text-8})=(1\times5)\times(10^{20}\times10^{\text-8})=5\times10^{12}.