Calculate the sample mean of x without the use of mean(), sd(), sum(), or . Hint: Recall that vectors in R are column vectors. (Although when you display them, they often look like row vectors.) You may need to create a second vector, which is allowed, and should also look into the function crossprod(). Essentially, you need to use matrix algebra to recreate the formulas above. You may use mean() to check your answer.

[a] create a class called “cycle” which has two instance integer variables as properties, “numberofwheels” and “weight.” create a constructor with two parameters, using the same variable names in the parameter list. assign each variable to numberofwheels” and “weight” respectively. write a separate application to test the class and display its properties. note: do not change the names of the instance variables or the variables listed in the constructor’s parameter list. [b] edit your class cycle by adding a default constructor which will assign the default values of 100 to represent the numberofwheels, and 1000 to represent the weight, by invoking a call to the other constructor. modify your application created in [a] to test the class.

Which of these is most responsible for differences between the twentieth century to the twenty-first century?

What are some ways to use a range name in a formula? check all that apply. in the defined names group, click use in formula, and then select the desired name. begin typing the name in the formula, select a name from the autocomplete list, and use the arrow keys and tab key to enter the name in the formula. begin typing the formula, and then click and drag with the mouse to select the cells to include in the formula. right-click one of the cells in the range. click formula options, and use the dialog box to add the name.