10 LET X = 100 // BALL 20 LET Y = 30 // BALL 30 LET U = - 7 //BALL SPEED 40 LET V = 10 //BALL SPEED 50 LET B = 40 //BALL SIZE 60 WAIT 8 70 COLOR BLACK ,BLACK 80 BOX X ,Y ,X + B ,Y + B 90 LET X = X + V 100 LET Y = Y + U 110 COLOR RED ,RED 120 BOX X ,Y ,X + B ,Y + B 130 IF Y +U <= 1 THEN LET U = - U 140 IF Y >= 399- (B+U) THEN LET U = - U 150 IF X +V<= 1 THEN LET V = - V 160 IF X >= 399 - (B+V) THEN LET V = - V 170 GOTO 60 180