57. C 58. B 59. A 60. D 61. B 62. B 63. D 64. B 65. A 66. C
67. A 68. D 69. A 70. B 71. D 72. C 73. C 74. A 75. B 76. D
77. A 78. C 79. D 80. C 81. B 82. A 83. D 84. B 85. C 86. A
87. (that/which) they have no solutions/answers to till now// to which they haven’t found solutions/answers so far
88. What most parents are concerned about
89. lest/in case it should get cold// incase it gets /turns cold// in case of temperature dreop
90. decided/ decide to establish/found/launch/start their own businesses/enterprises/ projects/ undertakings
91. until a doctor discovered it by chance/happened to discover it
