Tim Henman claims Emma Raducanu must answer two questions about her fitness during this year’s Australian Open. The former Wimbledon semi-finalist has challenged the 21-year-old to prove she is mentally and physically ready for the rigours of a Grand Slam. Raducanu will take on the USA’s Shelby Rogers in the first round in Melbourne on Monday. It will be her first appearance at a major since crashing out of last year’s tournament in the second round. The Brit has struggled with form and injury since winning the US Open in 2021. Raducanu underwent surgery last April on both hands and her left a…