题目
题目

COMM_V 205 101 102 103 2025W1 Exam B2 (R) 2025W1 Final - Requires Respondus LockDown Browser

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Suppose you had a dataset (assigned to data frame object called df). You know that it has 100 observations with a single numerical column called a. All observations for a are equal to 100. You then run the following code: df$b <- df$a df$a <- 0 mean(df$a != df$b) What did R output when the entire code was executed successfully? [Fill in the blank]

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思路分析
Consider the setup: df has 100 observations in a single numeric column a, where every value of a is 100. When we run df$b <- df$a, we copy the current values of a into a new column b, so init......Login to view full explanation

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Suppose you had a dataset (assigned to data frame object called df). df has 100 observations with a single numerical column called col1. col1 value of each observation is equal to 10. You then run the following code: df$col2 <- df$col1 df$col1 <- 0 mean(df$col2) What did R output when the entire code was executed successfully? [Fill in the blank]

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