"; echo "$a
"; # 1. 023 = 2*8^1+3*8^0 = 19 echo "$b
"; # 2. 0x1000 = 4096 echo "$c
"; # 3. 0x0020 = 32 echo "$d
"; # 4. 16E2 = 1600 echo "$e
"; # 5. 5.5E4 = 55000 # 6. 0.3E-2 =0.003 # 7. 111.111E2 =11111.1 # 8. 5E6 = 5000000 ?>