In which sport is the term 'Dolphin Kick' commonly

What will come in place of (?) question mark in the given number series.

52, 61, 79, 106, 142, ? 

15.975 ×27.825 + (76.01)² + 12.98×18.426 = ?+ (79.09)²

What will come in the place of questions (?) mark in the following questions.

1279, 1265, ? , 1225, 1193, 1149

97, 75, 108, 64, ?, 53

59, 70, ?,  81, 37, 92

135, 148, ?, 184, 207, 236

12, 16, ?, 48, 76, 112

32, 52, 82, 124, 180, ?

124, 128, ?, 135, 110, 146

What value should come in the place of (?) in the following number series?

15, 21, ?, 41.16, 57.624