Answer:
2(-2)-5(-2)+12
-4-(-10)+12
6+12
18
Step-by-step explanation:
Answer:
Step-by-step explanation:
a=2d+3
b=3d-12
c=a+b so
c=2d+3+3d-12
c=5d-9
The answer is 2
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Answer:
a) 1.8 × 10^-12 cm³ or 1.8 × 10^-12 cubic meters
b) 7.1 × 10^-6 mm² or 7.1 × 10^-6 square millimeters
Step-by-step explanation:
a) We are assuming that the shape of the bacteria is a sphere.
Hence, Volume of the Sphere(Bacteria) = 4/3 × π × r³
Diameter = 1.5 μm
Radius = Diameter/2 = 1.5μm/2
= 0.75μm
We are told that the volume should be in cubic centimeters
Converting 0.75μm to centimeters
1 μm = 1 × 10^-4 cm
0.75 μm =
Cross Multiply
= 0.75 μm × 1 × 10^-4 cm/ 1 μm
= 0.000075cm
Volume of the Sphere(Bacteria) = 4/3 × π × r³
= 4/3 × π × (0.000075)³
= 1.767145867 × 10^-12 cm³
Approximately as 2 significant figures = 1.8 × 10^-12 cm³
b) The formula for the Surface area of a Sphere = 4πr²
Diameter = 1.5 μm
Radius = Diameter/2 = 1.5μm/2
= 0.75μm
We are told that the surface area should be in square millimeters
Converting 0.75μm to millimeters
1 μm = 0.001 mm
0.75 μm =
Cross Multiply
= 0.75 μm ×0.001mm/ 1 μm
= 0.00075mm
Surface Area of a Sphere
= 4 × π × r²
= 4 × π × 0.00075²
= 7.06858 ×10^-6 mm²
Approximately to 2 significant figures
= 7.1 × 10^-6 mm²
Answer:
-14
Step-by-step explanation: