PLS guys help me (i'm brazillian)

The milk is _______ (cold) in the fridge.
a) colder
b) coldier
c) more cold

Mike is ______ (slim) than you.
a) slimer
b) slimmer
c) slimier

He is _____ (happy) than Tom is.
a) happier
b) more happy
c) happy

I am really glad, you know. Even _________ (glad) than you think.
a) gladder
b) more glad
c) glader

She is ____________ (clever) than I thought.
a) clever
b) cleverer
c) more clever

He is getting more and ___________ (anxious): he applied for a job and he hasn't got an answer yet.
a) more anxious
b) anxiouser
c) anxiousier

Come in, friends! This restaurant is ___________ (good) than any other one.
a) better
b) good
c) gooder

The skirt is ________ (nice) than the blouse.
a) nice
b) nicer
c) more nicer

thx <3