Maurice bought an item of jewellery in November 2015 for £125,000. In 2020 the jewellery was stolen. As a result, Maurice's insurance company paid him £141,500 in May 2020. In June 2020 he spent £150,000 on the purchase of replacement jewellery and claimed that neither a gain nor a loss should arise on the disposal of the original jewellery.

(a) Compute the chargeable gain arising in March 2023 when the replacement jewellery is sold for £180,000.

(b) How would this computation differ if the jewellery bought in June 2020 had cost only £140,000 and Maurice had made an appropriate claim?