Answer:
At an angle of 
Explanation:
Assume the river flows from East to West so for the swimmer to cross across it, assume he crosses it from West to East.
The resultant speed will be given by

Answer:
From question (a) and (b) the pendulum motion is perpendicular to the force so the normal force will do no work and the tension in the string of the pendulum will not work

And
so

c
An example will be a where a stone is attached to the end of a string and is made to move in a circular motion while keeping the other end of the string in a fixed position
d
A dog walking along a surface which has friction, here the frictional force would acting in the direction of the motion and this would do positive work
Explanation:
Answer:
HERE IS YOUR ANSWER
Explanation:
PLEASE MARK MY ANSWER AS BRAINLIEST IF THE ANSWERS ARE CORRECT .
Beacuse of the loose connection of the wire .
Straight
Explanation:
an echo mimics exactly what is said, this is like a mirror because when you look in a mirror every action you make is copied by your reflection
The answer to it is the letter A