Mehedi's teenage five-for, and Batty's time gap

There were ten DRS reviews in England's first innings at Chittagong - this must have been a record?! asked Derek Giles from England
The remarkable run of reviews - most of them seemingly involving Moeen Ali - during England's first innings against Bangladesh in Chittagong last week did indeed constitute a new record for Tests. The previous mark seems to be eight, in Sri Lanka's first innings of 388 against Pakistan in Dubai in 2013-14. India's S Ravi, the hard-pressed third official in the Chittagong Test, was one of the on-field umpires in Dubai.

Was Mehedi Hasan the youngest bowler to take five wickets in an innings on Test debut? asked Feroze Hossain from Bangladesh
Bangladesh's precocious new offspinner Mehedi Hasan was five days short of his 19th birthday when he took five wickets on the first day of his Test debut, against England in Chittagong last week. He ended up next day with 6 for 80. Three younger bowlers have taken debut five-fors. Shahid Nazir was 18 years and 319 days old when he claimed 5 for 53 for Pakistan against Zimbabwe in Sheikhupura in 1996-97, while another Pakistan cricketer, Shahid Afridi, was 18 years and 236 days when he took 5 for 52 in his first Test, against Australia in Karachi in 1998-99. But the youngest debutant of all to do it was Australian Pat Cummins, aged 18 years and 196 days when he took 6 for 79 against South Africa in Johannesburg in 2011-12 - in what, sadly, remains his only Test to date, because of various injuries.

The youngest bowler to take a five-for in any Test was Nasim-ul-Ghani, who was only 16 when he took 5 for 116 for Pakistan against West Indies in Georgetown in 1957-58 - that was his fourth Test, having made his debut earlier in the series. A slow left-armer, Nasim added 6 for 67 in the fifth Test in Port-of-Spain. Another Pakistani, Mohammad Amir, was only 17 when he took 5 for 79 against Australia in Melbourne in 2009-10, in his seventh Test. In all, 12 bowlers have taken Test five-fors when younger than Mehedi. The only other Bangladeshi to do it was Enamul Haque junior, against Zimbabwe in 2004-05, not long after his 18th birthday.

The BBC's Test Match Special statistician Andrew Samson revealed that the only spinner to take more wickets than Mehedi on his first day of Test cricket was Alf Valentine, the West Indian slow left-armer, who took the first eight to fall on his debut against England at Old Trafford in 1950. The only other one to take five was slow left-armer Albert Rose-Innes, in South Africa's inaugural Test, against England in Port Elizabeth in 1888-89.

Gareth Batty broke the record for the longest gap between Test appearances, but who holds the same record in ODIs and Twenty20s? asked Savo Ceprnich from South Africa
England played 142 Tests between Gareth Batty's seventh Test - against Bangladesh in Chester-le-Street in June 2005 - and his eighth, after his recall for the first match of the current series, in Chittagong. That broke the previous record for matches missed, 114 by Martin Bicknell for England between 1993 and 2003.

The equivalent record for one-day internationals is a dizzying 271 matches missed, by New Zealand's Jeff Wilson between 1992-93 and 2004-05. "Goldie" Wilson had a pretty good excuse: he was carving out a very successful rugby career with the New Zealand All Blacks during most of that time. Floyd Reifer missed 254 West Indies ODIs between 1998-99 and his recall in 2009, as captain during a contracts dispute. The record for T20 internationals is currently held by England's Liam Plunkett, who missed 74 between June 2006 and November 2015. He was run close earlier this year by Farveez Maharoof, who was recalled by Sri Lanka in July after missing 72 T20 internationals.

Batty's time gap between Test appearances - 11 years and 137 days - was noteworthy, but not a record: he's only 17th on that particular list. John Traicos went 22 years and 222 days between Test appearances (for South Africa in 1969-70 and Zimbabwe in 1992-93), while England batsman George Gunn played no Tests for almost 18 years between 1911-12 and 1929-30, when he was 50.

Gareth Batty opened the bowling in both innings of his comeback Test at Chittagong. Who was the last England spinner to do this? asked Kamran Muhammad from Pakistan
This is, as you suspect, quite rare - although Mehedi Hasan also did it for Bangladesh in Chittagong - and the last England slow bowler to do it before Batty is hardly a household name. It was the Nottinghamshire offspinner Sam Staples, in the last of his three Test appearances, against South Africa in Durban in 1927-28. He took 3 for 96 and 1 for 30 as South Africa won the match and squared the series 2-2. The list of those to have done it includes Kumar Dharmasena, one of the umpires in Chittagong, who took the new ball in both innings for Sri Lanka against Australia in Galle in March 2004. He wasn't very successful (2 for 52 and 0 for 100), and it turned out to be the last of his 31 Test matches as a player.

Which current umpire has stood in the most internationals? asked Rajan Gokhale from India
The only current umpire to have stood in more than 100 Tests is Aleem Dar, with 105; overall, he is behind only Steve Bucknor (128 between 1989 and 2009) and Rudi Koertzen (108 between 1992 and 2010). There's a long gap to the next member of the current elite umpires' panel, Ian Gould, who has stood in 53 Tests so far, although Billy Bowden, who stood in a Test in 2015, has done 84 in all. Koertzen stood in a record 209 one-day internationals, while Bowden umpired his 200th earlier this year; Aleem Dar is currently on 182, but he does lead the way for T20Is with 41. Overall, Dar has umpired 328 international matches in all three formats, and is set to overtake Koertzen's grand total of 331 soon. Bucknor (309) and Bowden (308) come next.

What's the fastest hundred by a wicketkeeper in one-day internationals? asked Ajay Avachare from India
The fastest hundred in all one-day internationals was smashed in just 31 balls by AB de Villiers for South Africa against West Indies in Johannesburg in January, 2015 - and, in addition to captaining, AB also kept wickets in that game. The record he broke, as far as wicketkeepers are concerned, was set by another South African in September, 2006: Mark Boucher sprinted to three figures in only 44 balls against Zimbabwe in Potchefstroom. Boucher remains fourth on the overall list, behind only de Villiers, Corey Anderson (36 balls) and Shahid Afridi (37).