Answer:
21
Step-by-step explanation:
PART A:
Scientific notation is given by A×10ⁿ where A is any number in a unit and 'n' is an integer.
0.000025 = 2.5×10⁻⁵
PART B:
Diameter of grain of sand ÷ Diameter of human body average cell
(2×10⁻⁴) ÷ (1×10⁻⁵)
(2÷1) × (10⁻⁴÷10⁻⁵)
2 × (10⁻⁴ ⁻ ⁻⁵) = 2 × 10⁽⁻⁴⁺⁵⁾ = 2 × 10¹ = 20 times bigger
PART C:
The diameter of human body's average cell in nanometer
1 × 10⁻⁵ metre = 1 × 10⁻⁵ × 10⁹ = 1 × 10⁽⁻⁵⁺⁹⁾ = 1 × 10⁴ nanometer
PART D:
Smallest bacteria = 300 nanometer
300 nm = 300 ÷ 10⁹ = (3 × 10²) ÷ 10⁹ = 3 × (10²⁻⁹) = 3 × 10⁻⁷ meter
PART E:
Laws of exponents that are applied in scientific notation is
xᵇ × xᵃ = x⁽ᵇ⁺ᵃ⁾
xᵇ ÷ xᵃ = x⁽ᵇ⁻ᵃ⁾
Part A
1 day = 1/4 hours of practice
7 days = 7/4 hours of practice (multiply both sides by 7)
1 week = 7/4 hours of practice
1 week = (4+3)/4 hours of practice
1 week = (4+3)/4 hours of practice
1 week = (4/4)+(3/4) hours of practice
1 week = 1+(3/4) hours of practice
1 week = 1 & 3/4 hours of practice
side note: 1 & 3/4 = 1.75
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Part B
Take the result from part A, and multiply it with 60
So we'll have 60 times 1&3/4 on the left side on the first line, then 60*(1+3/4) on the right side of this same line.
The rest of the lines look like this
(60*1) + (60*3/4)
60 + 60*3/4
60 + 180/4
60 + 45
105 minutes
You have to show us the graph or chart before we can answer your questions
-converting to a common denominator
The terms -c of the left side was converted to -4ac/4a to have the same denominator of b^2/4a.