Sunday Express �1000 Crossword.only 4 to do 10 across A riot is a spontaneous blank ? Richard Nixon O-T--R-T 20 across a Philippine plant -B---A 31 ACROSS A synthetic rubber used in waterproof products .N-O--E-E 33 across geometry- aline intersecting 2 or more lines T-A-S--R--L. Thanks in anticipation