Physics Questions-Force-1

As shown in the image, a W weight is hanged to the xyz string's y point.If the system is in balance, then what is the tension of xy string? Select from the following:

1. wcos30
2. wcos60
3. wtan30
4. wtan60
5. wsin60

Physics Qyestion 10

Water of a river, that is 1000m wide and has parallel banks, flows towards north in a constant velocity of 2ms-1. A man rows a boat from a place in a bank with a constant velocity of 3ms-1 to the east, relative to the water.

1. What is the boat's velocity relative to earth?
2. When the boat reaches the next bank, what is the distant it has flowed down the river?
3. What is the time taken for the man to cross the river?

If the man wants to get to the point perpendicular to the point he starts rowing, with all the other vectors same as above,

1. What is the direction he has to row the boat?
2. Then, what is the boat's velocity relative to the earth?
3. What is the time taken for the man to reach the other bank of the river?