B would be the best answer
Answer:
given statement is false
Step-by-step explanation:
given data
first time = 100 minutes
fourth time = 81 minutes
solution
as here time for 1st unit is multiply by learning percentage for obtain time for 2nd unit
so here time for 2nd unit divide by time of 1st unit so 100 is here learning curve
so
× 100 = 81 percent
but it say 90 percent learning curve
so given statement is false
Answer:
we conclude that the first step is to find the greatest common factor (GCF).
Hence, option C is correct.
Step-by-step explanation:

As 4 is the greatest common factor of the expression, so factor out common term 4:
i.e.

Thus, the first step is to find the greatest common factor (GCF)
Now, solving the remaining portion

as (2x+3) and (2x-3) are the factors of (4x²-9)
i.e. (4x²-9) = (2x+3) (2x-3)
Thus, the expression becomes

Therefore, we conclude that the first step is to find the greatest common factor (GCF).
Hence, option C is correct.
Answer:
Step-by-step explanation:

Answer:
Step-by-step explanation:
To determine the time when the height is 40 meters above the ground, we would substitute 40 for h in the given equation. It becomes
1.2 + 4t0t - 5t² = 40
5t² - 40t + 40 - 1.2 = 0
5t² - 40t + 38.8 = 0
The general formula for solving quadratic equations is expressed as
x = [- b ± √(b² - 4ac)]/2a
From the equation given,
a = 5
b = - 40
c = 38.8
Therefore,
t = [- - 40 ± √(- 40² - 4 × 5 × 38.8)]/2 × 5
t = [40 ± √(1600 - 776)]/10
t = [40 ± √824]/10
t = (40 + 28.71)/10 or x = (40 - 28.71)/10
t = 6.871 seconds or t = 1.129 seconds