What links Horrible Histories and Gordon Brown’s neighbour? The bumper summer quiz

The questions1 What is now the world’s most populous city, according to the UN?2 Which two Julies won best actress Oscars in consecutive years?3 What was thrown by the goddess Eris at the wedding of Peleus and Thetis?4 Richard Nixon appeared a record 55 times on the cover of what?5 What became Britain’s tallest structure in 1894?6 Mojang Studios in Sweden is renowned for developing which video game?7 Which golfer spent 270 weeks as world No 2, but never reached No 1?8 Which “The” group, named after a Camus novel, went through over 65 members?9 Who is the subject of Alberto Korda’s photograph Guerrillero Heroico?10 What defines an Olimpico goal in football?11 Who initiated the Fridays for Future school strikes?12 Which British dynasty is commemorated by a monument in St Peter’s Basilica?13 What type of souvenir was invented in Vienna in 1900?14 Which Norwegian island gives its name to two shipping forecast areas?15 Which art museum employs a colony of cats to protect it from rodents?16 Millvina Dean, who died in 2009, was the last living survivor of what?What links: 17 Arrival of spring; double portraits; swimming pools; Grand Canyon; Yorkshire landscape?18 Mozart & Franz Süssmayr; Landseer & Millais; F Scott Fitzgerald & Edmund Wilson?19 Cordelia, Goneril & Regan; Imogen; Marina?20 Britannia (1717-1936); Golden Hind (1937-69); St Edward’s Crown (1971-84)?21 Alba white truffles; Pule cheese; Wagyu beef; Yubari King melons?22 Matt Damon; Robert Frost; Bill Gates; Bonnie Raitt; Mark Zuckerberg?23 Horrible Histories; glucose; Gordon Brown’s neighbour; King-Smith’s swine; winter squash?24 Mount Whitney in California and Mulhacén in Andalucía?25 1991 defence of Baghdad; nacre; UK parliament; Virginia?26 Carrying a double bass; missing a bus; walking two dogs; wearing a cowboy hat; winding a clock?27 2 (1st); 29 (10th); 541 (100th); 7,919 (1,000th); 104,729 (10,000th)?28 Ant; bull; cuckoo; eagle; shower of gold; swan?29 Zlín, Czechoslovakia; Cohutta, US; Novo Mesto, Yugoslavia?30 Drowned; large bread; pick me up; half cold?What does the Grand Canyon have in common with the arrival of spring? Photograph: Robin Runck/AlamyThe answers1 Jakarta, Indonesia2 Julie Andrews (1965) and Julie Christie (1966)3 Golden apple (apple of discord)4 Time magazine5 Blackpool Tower6 Minecraft7 Phil Mickelson (behind Tiger Woods)8 The Fall9 Che Guevara10 Direct from a corner kick (without touching another player)11 Greta Thunberg12 Stuarts13 Snow globe14 Utsira (North and South Utsire)15 The Hermitage, St Petersburg16 Sinking of the Titanic17 David Hockney themes18 Latter completed/edited the former’s work after their death: Requiem; various paintings; The Last Tycoon19 Daughters of title characters in Shakespeare plays: King Lear, Cymbeline, Pericles20 Designs on the reverse of the halfpenny coin21 Expensive foodstuffs22 Harvard/Radcliffe dropouts23 Terms of endearment: (Terry) Deary, sugar, (Alistair) Darling, Babe, pumpkin24 Highest peaks in the Sierra Nevada mountain ranges (US and Spain)25 Known as Mother of … : Mother of all battles, mother-of-pearl, mother of parliaments, Mother of Presidents (nickname)26 Alfred Hitchcock cameos: Strangers on a Train, North by Northwest, The Birds, Psycho, Rear Window27 Prime numbers28 Forms variously taken by the god Zeus29 Birthplaces of wives of Donald Trump: Ivana, Marla, Melania30 Meanings of the names of Italian desserts: affogato, panettone, tiramisu, semifreddo