In books 1 through 4 of his "Elements", he covered the rudiments of plane geometry
Euclid
Though the show has ended, Joss Whedon still writes graphic novels about Angel & this title character
Buffy
Elementary classroom culture & management is an offering from Stanford's school of this
Education

A 17th-century holder of this holy office in a 20th-century portrait
the pope
This "pleased" company is known for its drawstring trash bags
Glad
Two or more circles that have the same center point are said to be this, from the Latin for "together center"
concentric
"The Photographer" Chronicles a trip to Afghanistan with this medical humanitarian organization
Doctors Without Borders
In the name of a Penn department, Earth Studies is paired with these earth-friendly studies
Environmental Studies
This English king in his coronation robes, a 1760 work by Allan Ramsay
George III
Rapture, or the first name of Ms. Behar of "The View"... so what? who cares?
Joy
You deserve straight As if you know that a straight angle has this many degrees
180
A graphic novel by Robert Venditti & Brett Weldele was the basis for this Bruce Willis film about androids that live for users
Surrogates
Don't bug me! I'm doing my reading for this class in which we study insects
entomology

This person seen here by Rembrandt, not Whistler
In titles, it precedes "Adventures of Robin Hood" & "Wives of Windsor"
Merry

Because the angle here is more than 90 degrees, both the angle & the triangle are classified as this
obtuse
Tim Hamilton illustrated the authorized adaptation of this dystopian classic by Ray Bradbury
Fahrenheit 451
At Harvard, Introduction to Game Theory is a course on this
economics
This super-impressionist, by fellow painter Renoir, 1875
Monet
Greatly pleased, you're said to be this verb "pink" but to me, that sounds awful!
tickled
When carried out to 5 decimal places, pi equals this
3.14159
Art Spiegelman tackled the holocaust in this graphic novel that portrayed Germans as cats
Maus
Often paired with public health, it's the branch of medicine that deals with outbreaks of infectious diseases
epidemiology

Seen here, Giovanni, a younger member of this Tuscan family
the de'Medicis
Ron Burgundy sang--but I won't--"a-uh-aa-aa-aa... afternoon" this
delight