7. use the aggregate() function to compute the sample sizes (ozn), means (ozm), and standard deviations (ozsd) for the control and ozone treatment groups, and then compute the standard errors (ozse) for both groups. make sure the numeric values are visible in your output. copy/paste your r commands and the resulting output into the green box below. (1 point)

only #2 represents an object at rest on a table.

in #1, there is no normal force due to the table; the object is accelerating downward.

in #3, the vertical forces are not balanced; the object is accelerating downward.

in #4, neither the vertical nor the horizontal forces are balanced. the object is accelerating upwards and to the right.

do not use any of these common illegal characters/symbols:

# pound

% percent

& ampersand

{ left curly bracket

} right curly bracket

\ back slash

< left angle bracket

> right angle bracket

* asterisk

? question mark

/ forward slash

  blank spaces

$ dollar sign

! exclamation point

' single quotes

" double quotes

: colon

@ at sign