<div class="user_solution"><p><strong>1. b7</strong></p><p> 1. Kc7 a2 2. Nb3 Rg7+ 3. Kxc6 a1=Q 4. Nxa1 Rg3 =</p><p></p><p><strong>1... Rg8+</strong> </p><p> 1... a2 2. Rxc6+ +- </p><p><strong>2. Kc7 Rg7+ 3. Kxc6 Rxb7 4. Kc5+ Ka5 5. Nc6+ Ka4 6. Rh4+ Kb3 7.</strong><strong> </strong><strong>Na5+ Kc3 8. Rh3+!</strong> </p><p></p><p> 8. Nxb7? a2 9. Rh3+ Kb2 10. Rh2+ Ka3 </p><p><strong>8... Kb2 9. Rh2+!</strong> </p><p>      9. Nxb7? a2 10. Rh2+ Ka3 </p><p><strong>9... Kb1 10. Nxb7 a2 11. Kb4 a1=Q 12. Kb3</strong> with win<br /></p><br /></div>