49.
1). will be launched
2). launched
3). is launched
4). has launched

50.
1). used
2). be used
3). have been used
4). be using

51.
1). raise
2). will be raising
3). were raising
4). will raise

52.
1). due to
2). despite
3). even with
4). in light

53.
1). can
2). should
3). would
4). might​