OK, let's crack this. We're given 140 and our task is to multiply it by 256. Essentially, we'll be adding 140 to itself 256 times.
Step 1: 0 + 140 = 140
Step 2: 140 + 140 = 280
Step 3: 280 + 140 = 420
Step 4: 420 + 140 = 560
Step 5: 560 + 140 = 700
Step 6: 700 + 140 = 840
Step 7: 840 + 140 = 980
Step 8: 980 + 140 = 1120
Step 9: 1120 + 140 = 1260
Step 10: 1260 + 140 = 1400
Step 11: 1400 + 140 = 1540
Step 12: 1540 + 140 = 1680
Step 13: 1680 + 140 = 1820
Step 14: 1820 + 140 = 1960
Step 15: 1960 + 140 = 2100
Step 16: 2100 + 140 = 2240
Step 17: 2240 + 140 = 2380
Step 18: 2380 + 140 = 2520
Step 19: 2520 + 140 = 2660
Step 20: 2660 + 140 = 2800
Step 21: 2800 + 140 = 2940
Step 22: 2940 + 140 = 3080
Step 23: 3080 + 140 = 3220
Step 24: 3220 + 140 = 3360
Step 25: 3360 + 140 = 3500
Step 26: 3500 + 140 = 3640
Step 27: 3640 + 140 = 3780
Step 28: 3780 + 140 = 3920
Step 29: 3920 + 140 = 4060
Step 30: 4060 + 140 = 4200
Step 31: 4200 + 140 = 4340
Step 32: 4340 + 140 = 4480
Step 33: 4480 + 140 = 4620
Step 34: 4620 + 140 = 4760
Step 35: 4760 + 140 = 4900
Step 36: 4900 + 140 = 5040
Step 37: 5040 + 140 = 5180
Step 38: 5180 + 140 = 5320
Step 39: 5320 + 140 = 5460
Step 40: 5460 + 140 = 5600
Step 41: 5600 + 140 = 5740
Step 42: 5740 + 140 = 5880
Step 43: 5880 + 140 = 6020
Step 44: 6020 + 140 = 6160
Step 45: 6160 + 140 = 6300
Step 46: 6300 + 140 = 6440
Step 47: 6440 + 140 = 6580
Step 48: 6580 + 140 = 6720
Step 49: 6720 + 140 = 6860
Step 50: 6860 + 140 = 7000
Step 51: 7000 + 140 = 7140
Step 52: 7140 + 140 = 7280
Step 53: 7280 + 140 = 7420
Step 54: 7420 + 140 = 7560
Step 55: 7560 + 140 = 7700
Step 56: 7700 + 140 = 7840
Step 57: 7840 + 140 = 7980
Step 58: 7980 + 140 = 8120
Step 59: 8120 + 140 = 8260
Step 60: 8260 + 140 = 8400
Step 61: 8400 + 140 = 8540
Step 62: 8540 + 140 = 8680
Step 63: 8680 + 140 = 8820
Step 64: 8820 + 140 = 8960
Step 65: 8960 + 140 = 9100
Step 66: 9100 + 140 = 9240
Step 67: 9240 + 140 = 9380
Step 68: 9380 + 140 = 9520
Step 69: 9520 + 140 = 9660
Step 70: 9660 + 140 = 9800
Step 71: 9800 + 140 = 9940
Step 72: 9940 + 140 = 10080
Step 73: 10080 + 140 = 10220
Step 74: 10220 + 140 = 10360
Step 75: 10360 + 140 = 10500
Step 76: 10500 + 140 = 10640
Step 77: 10640 + 140 = 10780
Step 78: 10780 + 140 = 10920
Step 79: 10920 + 140 = 11060
Step 80: 11060 + 140 = 11200
Step 81: 11200 + 140 = 11340
Step 82: 11340 + 140 = 11480
Step 83: 11480 + 140 = 11620
Step 84: 11620 + 140 = 11760
Step 85: 11760 + 140 = 11900
Step 86: 11900 + 140 = 12040
Step 87: 12040 + 140 = 12180
Step 88: 12180 + 140 = 12320
Step 89: 12320 + 140 = 12460
Step 90: 12460 + 140 = 12600
Step 91: 12600 + 140 = 12740
Step 92: 12740 + 140 = 12880
Step 93: 12880 + 140 = 13020
Step 94: 13020 + 140 = 13160
Step 95: 13160 + 140 = 13300
Step 96: 13300 + 140 = 13440
Step 97: 13440 + 140 = 13580
Step 98: 13580 + 140 = 13720
Step 99: 13720 + 140 = 13860
Step 100: 13860 + 140 = 14000
Step 101: 14000 + 140 = 14140
Step 102: 14140 + 140 = 14280
Step 103: 14280 + 140 = 14420
Step 104: 14420 + 140 = 14560
Step 105: 14560 + 140 = 14700
Step 106: 14700 + 140 = 14840
Step 107: 14840 + 140 = 14980
Step 108: 14980 + 140 = 15120
Step 109: 15120 + 140 = 15260
Step 110: 15260 + 140 = 15400
Step 111: 15400 + 140 = 15540
Step 112: 15540 + 140 = 15680
Step 113: 15680 + 140 = 15820
Step 114: 15820 + 140 = 15960
Step 115: 15960 + 140 = 16100
Step 116: 16100 + 140 = 16240
Step 117: 16240 + 140 = 16380
Step 118: 16380 + 140 = 16520
Step 119: 16520 + 140 = 16660
Step 120: 16660 + 140 = 16800
Step 121: 16800 + 140 = 16940
Step 122: 16940 + 140 = 17080
Step 123: 17080 + 140 = 17220
Step 124: 17220 + 140 = 17360
Step 125: 17360 + 140 = 17500
Step 126: 17500 + 140 = 17640
Step 127: 17640 + 140 = 17780
Step 128: 17780 + 140 = 17920
Step 129: 17920 + 140 = 18060
Step 130: 18060 + 140 = 18200
Step 131: 18200 + 140 = 18340
Step 132: 18340 + 140 = 18480
Step 133: 18480 + 140 = 18620
Step 134: 18620 + 140 = 18760
Step 135: 18760 + 140 = 18900
Step 136: 18900 + 140 = 19040
Step 137: 19040 + 140 = 19180
Step 138: 19180 + 140 = 19320
Step 139: 19320 + 140 = 19460
Step 140: 19460 + 140 = 19600
Step 141: 19600 + 140 = 19740
Step 142: 19740 + 140 = 19880
Step 143: 19880 + 140 = 20020
Step 144: 20020 + 140 = 20160
Step 145: 20160 + 140 = 20300
Step 146: 20300 + 140 = 20440
Step 147: 20440 + 140 = 20580
Step 148: 20580 + 140 = 20720
Step 149: 20720 + 140 = 20860
Step 150: 20860 + 140 = 21000
Step 151: 21000 + 140 = 21140
Step 152: 21140 + 140 = 21280
Step 153: 21280 + 140 = 21420
Step 154: 21420 + 140 = 21560
Step 155: 21560 + 140 = 21700
Step 156: 21700 + 140 = 21840
Step 157: 21840 + 140 = 21980
Step 158: 21980 + 140 = 22120
Step 159: 22120 + 140 = 22260
Step 160: 22260 + 140 = 22400
Step 161: 22400 + 140 = 22540
Step 162: 22540 + 140 = 22680
Step 163: 22680 + 140 = 22820
Step 164: 22820 + 140 = 22960
Step 165: 22960 + 140 = 23100
Step 166: 23100 + 140 = 23240
Step 167: 23240 + 140 = 23380
Step 168: 23380 + 140 = 23520
Step 169: 23520 + 140 = 23660
Step 170: 23660 + 140 = 23800
Step 171: 23800 + 140 = 23940
Step 172: 23940 + 140 = 24080
Step 173: 24080 + 140 = 24220
Step 174: 24220 + 140 = 24360
Step 175: 24360 + 140 = 24500
Step 176: 24500 + 140 = 24640
Step 177: 24640 + 140 = 24780
Step 178: 24780 + 140 = 24920
Step 179: 24920 + 140 = 25060
Step 180: 25060 + 140 = 25200
Step 181: 25200 + 140 = 25340
Step 182: 25340 + 140 = 25480
Step 183: 25480 + 140 = 25620
Step 184: 25620 + 140 = 25760
Step 185: 25760 + 140 = 25900
Step 186: 25900 + 140 = 26040
Step 187: 26040 + 140 = 26180
Step 188: 26180 + 140 = 26320
Step 189: 26320 + 140 = 26460
Step 190: 26460 + 140 = 26600
Step 191: 26600 + 140 = 26740
Step 192: 26740 + 140 = 26880
Step 193: 26880 + 140 = 27020
Step 194: 27020 + 140 = 27160
Step 195: 27160 + 140 = 27300
Step 196: 27300 + 140 = 27440
Step 197: 27440 + 140 = 27580
Step 198: 27580 + 140 = 27720
Step 199: 27720 + 140 = 27860
Step 200: 27860 + 140 = 28000
Step 201: 28000 + 140 = 28140
Step 202: 28140 + 140 = 28280
Step 203: 28280 + 140 = 28420
Step 204: 28420 + 140 = 28560
Step 205: 28560 + 140 = 28700
Step 206: 28700 + 140 = 28840
Step 207: 28840 + 140 = 28980
Step 208: 28980 + 140 = 29120
Step 209: 29120 + 140 = 29260
Step 210: 29260 + 140 = 29400
Step 211: 29400 + 140 = 29540
Step 212: 29540 + 140 = 29680
Step 213: 29680 + 140 = 29820
Step 214: 29820 + 140 = 29960
Step 215: 29960 + 140 = 30100
Step 216: 30100 + 140 = 30240
Step 217: 30240 + 140 = 30380
Step 218: 30380 + 140 = 30520
Step 219: 30520 + 140 = 30660
Step 220: 30660 + 140 = 30800
Step 221: 30800 + 140 = 30940
Step 222: 30940 + 140 = 31080
Step 223: 31080 + 140 = 31220
Step 224: 31220 + 140 = 31360
Step 225: 31360 + 140 = 31500
Step 226: 31500 + 140 = 31640
Step 227: 31640 + 140 = 31780
Step 228: 31780 + 140 = 31920
Step 229: 31920 + 140 = 32060
Step 230: 32060 + 140 = 32200
Step 231: 32200 + 140 = 32340
Step 232: 32340 + 140 = 32480
Step 233: 32480 + 140 = 32620
Step 234: 32620 + 140 = 32760
Step 235: 32760 + 140 = 32900
Step 236: 32900 + 140 = 33040
Step 237: 33040 + 140 = 33180
Step 238: 33180 + 140 = 33320
Step 239: 33320 + 140 = 33460
Step 240: 33460 + 140 = 33600
Step 241: 33600 + 140 = 33740
Step 242: 33740 + 140 = 33880
Step 243: 33880 + 140 = 34020
Step 244: 34020 + 140 = 34160
Step 245: 34160 + 140 = 34300
Step 246: 34300 + 140 = 34440
Step 247: 34440 + 140 = 34580
Step 248: 34580 + 140 = 34720
Step 249: 34720 + 140 = 34860
Step 250: 34860 + 140 = 35000
Step 251: 35000 + 140 = 35140
Step 252: 35140 + 140 = 35280
Step 253: 35280 + 140 = 35420
Step 254: 35420 + 140 = 35560
Step 255: 35560 + 140 = 35700
Step 256: 35700 + 140 = 35840

So, 140*256 = 35840