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.

Write a function so that the main0 code below can be replaced by the simpler code that calls function mphandminutes tomiles0. original main0 int main) l double milesperhour-70.0; double minutestraveled = 100.0; double hourstraveled; double milestraveled; hourstraveled = minutestraveled / 60.0; milestraveled = hourstraveled * milesperhour; cout < "miles" 2 using namespace std; 4 /* your solution goes here/ 6 int maino 1 test passed 7 double milesperhour 70.0 all tests passed 8 double minutestraveled 100.0; 10 cout < < "miles: " < < mphandminutestomiles(milesper-hour, minutestraveled) < < endl; 12 return 0; 13