A sports shop in Manchester is doing a sale on some merchandise. Liz hears about it and goes to make a purchase of two pairs of running shoes. She gives the sales attendant in the store three crisp 50 notes and is given change of 10.50. What is the price of each pair of running shoes? Show your working.

a) What is 240.50 x 19.54? Give your answer to 2 significant figures. (4 marks) b) Write the number 52100 as a power of 10.