I am pretty sure the height is 4, but sorry if i am wrong
System of equations subtraction method
In the addition/subtraction method, the two equations in the system are added or subtracted to create a new equation with only one variable. ... Substitute the variable back into one of the equations and solve for the other variable. Check the solution--it should satisfy both equations.
Volume of a cone = (1/3) x Area of the base (B) x height(h)
V = (1/3)·420·180
= 25200 mm³
The parameter of interest in this scenario is the proportion of all 1,000 students within the school who have "strict" parents or guardians.
<h3>How to calculate a test statistic?</h3>
In Mathematics, the test statistics of a given sample is calculated by using this formula:

<u>Where:</u>
- is the standard deviation.
In conclusion, a possible test statistic which can be used to estimate this parameter is the proportion of all students who have "strict" parents or guardians, based on the collected sample.
Read more on test statistic here: brainly.com/question/4621112
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