Puzzle

 ACROSS

  1 Chatterbox's "gift"

  4 Sub, chips and a drink, e.g.

  9 They're often taken after all-nighters

 13 Lodes' contents

 15 Oteri who portrayed Judge Judy

 16 Somber news bio

 17 "Your approach to this math problem will never work!"

 19 Major streaming service

 20 101 course

 21 Full of typos, say

 23 Feeling on a hot day

 26 "Confound it!"

 27 "Don't let that hard math concept get you down!"

 32 Hour when daylight saving time starts

 35 Apple assistant

 36 Tone of an old photo

 37 Instrument in Guinness's logo

 39 Salsa or samba

 42 Diana of The Supremes

 43 Musical copyright org.

 45 Skin care brand

 47 Up time?

 48 "You're so talented in math!"

 52 Not yet eliminated

 53 Break free

 56 Like bungee cords

 60 Flings

 62 Office underling

 63 "I'll leave you to finish your math homework!"

 66 Band that aptly uses amps?

 67 Cross the threshold

 68 ___ Spumante

 69 The old you?

 70 Hideaways

 71 Dry, as cement

DOWN

  1 Asia's second-largest desert

  2 "___ you clever!"

  3 Marina offering

  4 Early third-century year

  5 "What have we here?!"

  6 Bookmarks or History, in a browser

  7 Marlon who refused an Oscar

  8 NHL team whose logo features a droplet

  9 Beautifully pitched game

 10 Adjoin

 11 Heap

 12 Good-looking dude

 14 Kolkata garments

 18 Legal wrongs

 22 Raised platform

 24 "___ no one ever"

 25 Banks with millions of dollars?

 28 Lead-in to "noir" or "gris"

 29 Walkman descendant

 30 Passport endorsement

 31 Hardly hard

 32 Defrost

 33 Laundry

 34 The whale in "Free Willy," for one

 38 Saintly virtue

 40 This one is self-referential

 41 Floppy parts of a bloodhound

 44 Breathe after a run

 46 Pleasure craft

 49 Coin that's actually 75% copper

 50 Goddess of wisdom

 51 First lady prior to Michelle

 54 Aggressive defense in basketball

 55 Send over the moon

 56 Tiff

 57 The "T" of MIT, informally

 58 Took, as a train

 59 Legendary Himalayan

 61 Narrow cut

 64 For each

 65 Form 1040 org.

Solution