<div>a) (1.Rc2? (<span id="solP1394598-4" style="background-color: transparent;">2.</span><span id="solP1394598-5" style="background-color: transparent;">b4+</span> <span id="solP1394598-6" style="background-color: transparent;">Kb1</span> <span id="solP1394598-7" style="background-color: transparent;">3.</span><span id="solP1394598-8" style="background-color: transparent;">Kb3</span> <span id="solP1394598-9" style="background-color: transparent;">cxb4</span> <span id="solP1394598-10" style="background-color: transparent;">4.</span><span id="solP1394598-11" style="background-color: transparent;">Bd3</span> <span id="solP1394598-12" style="background-color: transparent;">bxa3</span> <span id="solP1394598-13" style="background-color: transparent;">5.</span><span id="solP1394598-14" style="background-color: transparent;">c4</span> <span id="solP1394598-15" style="background-color: transparent;">a2</span> <span id="solP1394598-16" style="background-color: transparent;">6.</span><span id="solP1394598-17" style="background-color: transparent;">Rc3#</span>)</div><div>1... Kb1 2.Bd3 c4!)</div><div><br /></div><div>1.Bd3! c4 2.Be4 cxb3 3.Bf3 Kb1 4.Kxb3 Kc1 5.Rc2+ Kb1 6.Rd2 Kc1 7.Rd1#</div><div><br /></div><div>b) (1.Bd3??)</div><div><br /></div><div><b>1.Rc2!</b> Kb1 2.Bd3 Ka2 3.c4 Kb1 4.Kb5 Ka2 5.Rd2 Kxa3 6.Bb1 Kxb3 7.Rd3#</div><div>5... Kxb3 6.Bb1 Kxa3/Kc3 7.Rd3#</div><div><br /></div><div>c) (1.Bd3??)</div><div><br /></div><div><span id="solP1394598-80" style="background-color: transparent;">(1.</span><span id="solP1394598-81" style="background-color: transparent;">d4?</span> <span id="solP1394598-82" style="background-color: transparent;">cxd4</span> <span id="solP1394598-83" style="background-color: transparent;">2.</span><span id="solP1394598-84" style="background-color: transparent;">Rc2</span> <span id="solP1394598-85" style="background-color: transparent;">Kb1</span> <span id="solP1394598-86" style="background-color: transparent;">3.</span>B<span id="solP1394598-87" style="background-color: transparent;">d3</span> <span id="solP1394598-88" style="background-color: transparent;">Ka2</span> <span id="solP1394598-89" style="background-color: transparent;">4.</span><span id="solP1394598-90" style="background-color: transparent;">b4</span> <span id="solP1394598-91" style="background-color: transparent;">Kb1</span> <span id="solP1394598-92" style="background-color: transparent;">5.</span><span id="solP1394598-93" style="background-color: transparent;">Rc3+</span> <span id="solP1394598-94" style="background-color: transparent;">Ka2</span> <span id="solP1394598-95" style="background-color: transparent;">6.</span><span id="solP1394598-96" style="background-color: transparent;">Rb3</span> <span id="solP1394598-97" style="background-color: transparent;">b1=Q</span> <span id="solP1394598-98" style="background-color: transparent;">7.</span><span id="solP1394598-99" style="background-color: transparent;">Bxb1#</span> <br /><span id="solP1394598-100">2</span><span id="solP1394598-101" style="background-color: transparent;">...</span> <span id="solP1394598-102" style="background-color: transparent;">d3</span> 3.<span id="solP1394598-104" style="background-color: transparent;">Bxd3</span> (<span id="solP1394598-106" style="background-color: transparent;">4.</span><span id="solP1394598-107" style="background-color: transparent;">b4</span> <span id="solP1394598-108" style="background-color: transparent;">Kb1</span> <span id="solP1394598-109" style="background-color: transparent;">5.</span><span id="solP1394598-110" style="background-color: transparent;">Rc3+</span> <span id="solP1394598-111" style="background-color: transparent;">Ka2</span> <span id="solP1394598-112">6.</span><span id="solP1394598-113" style="background-color: transparent;">Rb3</span> <span id="solP1394598-114" style="background-color: transparent;">b1=Q</span> <span id="solP1394598-115" style="background-color: transparent;">7.</span><span id="solP1394598-116" style="background-color: transparent;">Bxb1#)</span> <br /><span id="solP1394598-117" style="background-color: transparent;">3.</span><span id="solP1394598-118" style="background-color: transparent;">..</span> <span id="solP1394598-119" style="background-color: transparent;">Kb1</span> <span id="solP1394598-120" style="background-color: transparent;">4.</span><span id="solP1394598-121" style="background-color: transparent;">Kb5</span> <span id="solP1394598-122" style="background-color: transparent;">Ka2</span> <span id="solP1394598-123" style="background-color: transparent;">5.</span><span id="solP1394598-124" style="background-color: transparent;">Rd2</span> <span id="solP1394598-125" style="background-color: transparent;">Kxa3/Kxb3</span> <span id="solP1394598-126" style="background-color: transparent;">6.</span><span id="solP1394598-127" style="background-color: transparent;">Rb1</span> <span id="solP1394598-128" style="background-color: transparent;">Kxb3/Kxa3,Kc3</span> <span id="solP1394598-129" style="background-color: transparent;">7.</span><span id="solP1394598-130" style="background-color: transparent;">Rd3#</span> <br /><span id="solP1394598-131" style="background-color: transparent;">1.</span>.<span id="solP1394598-132" style="background-color: transparent;">.</span> <span id="solP1394598-133" style="background-color: transparent;">Kb1!)</span></div><div> <br /></div><div><b>1. Rc2!</b> Kb1 2.Rc3 Ka2 3.b4+ Kb1 4.d4 cxb4 5.Bd3+ Ka2 6.Rb3 b1=Q 7.Bxb1#</div><div>6... bxa3 7.Rxa3#</div><div>4... cxd4 5.Bd3+ Ka2 6.Rb3 b1=Q 7.Bxb1#</div><br />