We need two more hands to ______ the heavy rush of work .

Fill in the blanks : We need______ to do any kind of work.

Two workers A and B are engaged to do a piece of work.Working alone, A takes 8 hours more to complete the workthan if both worked together. On the other hand, workingalone, B would need 4 1/2 hours more to complete the work than if both worked together. How much time would they take tocomplete the job working together?

Explain why, we can easily move our hand in air but to do the same through a plank of wood, we need a karate expert.

Give reasons. We can easily move our hand in air but to do the same through a solid block of wood we need a karate expert.