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1.

You have a tibble, or data frame, with the dimension 20, 2. What does this tell you about it?

The tibble consists of 20 rows and 2 columns.

The tibble contains 2 columns, with the values 2 and 20.

The tibble contains 20 rows, all with the value 2.

2.

You have a data frame named df_sales, which contains daily sales data. The data frame displays columns for year, month, day_of_month, and sales_total. You want to find the average sales_total value. Which code should you use?

df_sales %>% pull(sales_total) %>% avg()

mean(sales_total$df_sales)

mean(df_sales$sales_total)

3.

You have a data frame that displays data about daily ice cream sales. You use the R function cor to compare the avg_temp and units_sold columns, and you get a result of 0.97. What does this result indicate?

On the day with the maximum units_sold value, the avg_temp value was 0.97.

Days with high avg_temp values tend to coincide with days that have high units_sold values.

The units_sold value is, on average, 97 percent of the avg_temp value.

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