Answer:
The kinetic energy is 20,000\ J
Step-by-step explanation:
The kinetic energy of a body is defined as:

Where <em>m</em> is the mass of the roller coaster car
<em>s</em> is the speed and <em>k</em> is the kinetic energy
We know that 

Then the kinetic energy of the roller coaster car is:

Answer: A: there is not enough evidence to support a relationship between lunch preference and role at school
Don’t open that link above me bc they’ll track your ip address
Answer:
Do no reject null hypothesis.
Conclusion:
there is no sufficient statistical evidence at 0.025 level of significance to support the claim.
Step-by-step explanation:
Given that;
mean x" = 5.4
standard deviation σ = 0.7
n = 6
Null hypothesis H₀ : μ = 5.0
Alternative hypothesis H₁ : μ > 5.0
∝ = 0.025
now,
t = ( 5.4 - 5.0) / ( 0.7/√6) = 0.4 / 0.2857 = 1.4
degree of freedom df = n-1 = 6 - 1 = 5
T critical = 2.571
Therefore; t < T critical,
Do no reject null hypothesis.
Conclusion:
there is no sufficient statistical evidence at 0.025 level of significance to support the claim.
Answer:
5cm by 1.95cm
Step-by-step explanation:
Let the length of the rectangle be x
Let the width be y
Perimeter of a rectangle = 2x + 2y
If the initial perimeter of a rectangle is about 13.9 cm, then;
13.9 = 2x + 2y ..... 1
If when the width is double the perimeter is 17.8cm, then;
17.8 = 2x + 4y ..... 2
Subtract 1 from 2;
13.9 - 17.8 = 2y - 4y
- 3.9 = -2y
y = 3.9/2
y = 1.95 cm
Substitute y = 1.95 into 1 to get x;
From 1;
13.9 = 2x + 2y
13.9 = 2x + 2(1.95)
13.9 = 2x + 3.9
2x = 13.9-3.9
2x = 10
x = 5 cm
Hence the dimension of the smaller triangle is 5cm by 1.95cm