Another IE7 bug, or my mistake?

Here are URLs and screen shots. FF is doing the right thing across
the board. IE7 has six problems; see below. IE6 doesn't have
problems 1 through 4, but IE6 does have problems 5 and 6.

NOTE: The two browsers are set with different default fonts and
sizes; naturally I'm not concerned about those differences. Also,
IE6 ignores max-width, as discussed in a separate thread, but I'm not
concerned about that either.

I've validated the HTML (4.01 Strict) and the CSS at W3C with no
errors or warnings.

URL: http://www.tc3.edu/instruct/sbrown/stat/labshoe.htm
style sheet: http://www.tc3.edu/instruct/sbrown/screen.css

How it should look, and how it looks in Firefox3 and IE6:

http://www.tc3.edu/instruct/sbrown/stat/shoe_ff3.jpg

How it looks in IE7:

http://www.tc3.edu/instruct/sbrown/stat/shoe_ie7.jpg

Problems:

(1) "Summary" is to the left of where it should be.

(2) The text (beginning "It seems intuitively") has a blue background
and

(3) is in bold face and

(4) is centered.

(5) The first row of the table is broken into six lines when it could
easily fit on one, and

(6) it's left aligned instead of centered.


Thanks for any insights!

--
Stan Brown, Oak Road Systems, Tompkins County, New York, USA
http://OakRoadSystems.com/
HTML 4.01 spec: http://www.w3.org/TR/html401/
validator: http://validator.w3.org/
CSS 2.1 spec: http://www.w3.org/TR/CSS21/
validator: http://jigsaw.w3.org/css-validator/
Why We Won't Help You:
http://diveintomark.org/archives/2003/05/05/why_we_wont_help_you