Q1: On piles, the drop must be at least

ANS:C - 120 cm

The "drop" in the context of pile driving typically refers to the distance the hammer is allowed to fall before striking the pile. This drop height is important for ensuring proper penetration of the pile into the soil and for achieving the desired bearing capacity. The minimum drop height required for pile driving depends on various factors including the type of soil, the type and size of the pile, and the required bearing capacity. However, a common industry standard for the minimum drop height is typically around 150 cm (1.5 meters). So, among the options provided:

• 80 cm
• 100 cm
• 120 cm
• 140 cm
• 150 cm

The most appropriate answer would be: 120 cm This ensures sufficient energy transfer from the hammer to the pile for effective driving and penetration into the soil. However, it's worth noting that specific project requirements and soil conditions may dictate variations in the minimum drop height.